Digital Optical Microscopy Research Articles

Infrared on-site heating for material extrusion additive manufacturing of carbon fiber filled polyphenylene sulfide and its nano-graphene-reinforced alternatives

This study investigates the impact of infrared heating and annealing on the mechanical properties of carbon fiber-reinforced polyphenylene sulfide (CF-PPS) and graphene nanoplatelet (GNP)-reinforced CF-PPS composites in Material extrusion (MEX) additive manufacturing. GNP/CF-PPS composites are prepared by mechanically mixing CF-PPS plastic particles with GNP particles and subjecting them to infrared heating and annealing treatments during the three-dimensional (3D) printing process. Three-point bending tests assess the mechanical properties of the samples. The results reveal that the 0.03 wt.% GNP/CF-PPS sample, subjected to infrared heating followed by annealing, exhibits a 30% increase in bending strength compared to pure CF-PPS, demonstrating that the combined treatment significantly enhances mechanical performance. Microscopy observations using a Keyence VH7000 digital optical microscope and a scanning electron microscope (SEM) confirm that GNP addition and infrared irradiation lead to reduced surface roughness and fewer fracture cross-sectional pores. The interlayer bonding improves notably, indicating enhanced internal density and structural stability. Furthermore, differential scanning calorimetry analysis shows a 20% increase in crystallinity for heat-treated samples, contributing to better interlaminar bonding and reduced temperature gradients during printing. Finite element simulations using MATLAB and ABAQUS software corroborate these findings, demonstrating that infrared heating proves more effective than varying GNP content alone in reducing deformation, residual stress, and temperature differences during the MEX process. These results provide valuable insights into improving the mechanical properties and stability of MEX-manufactured large-dimensional composite materials through optimized thermal management.

Macroscopic observation of a first order one-dimensional swelling-deswelling transition in a nanolayered material

AbstractThe high purity and superior quality of the synthetic clay mineral fluorohectorite allows for studies of phenomena that are masked by imperfections and the inhomogeneous charge distribution in the case of natural clay minerals. We have exploited this opportunity offered by synthetic fluorohectorite and report here digital optical microscopy observations of salinity controlled macroscopic swelling and deswelling behavior of extra-large nanolamellar clay mineral particle accordions of various sizes. We find that clay particle accordions, immersed in a saline solution, at sufficiently high salinity, are in their crystalline swelling region, with only a few water layers hydrating the accordion interlayer nano-spaces, corresponding to an interlayer spacing of about 1.5 nm. Using a micropipette as a micro-tweezer and thereby transferring accordions carefully back and forth between high and low salinity solutions, we observe well defined macroscopic accordion transitions between the crystalline swelling regime and an osmotic swelling regime where the interlayer spacings reach tens of nanometers, calculated from accordion thicknesses measured by digital imaging. The transitions display a clear first order character as evidenced by threshold salinity levels for their abrupt onsets as well as clear hysteresis with retention of crystalline or osmotic state memory, as salinity is increased or lowered. The experimental observations are supported by a theoretical model of the accordion interlayer spacing based on a Donnan equilibrium originating from the salinity gradient between the embedding saline solution and the ionic strength in the clay interlayers in the osmotic swelling regime.

Effects of heat input on microstructure evolution and corrosion resistance of underwater laser cladding high-strength low-alloy steel coating

The effects of heat input on the microstructure evolution and corrosion resistance of the high-strength low-alloy (HSLA) steel coating obtained by wire-feed underwater laser cladding were studied. Optical digital microscope, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscope (TEM), electron back-scattered diffraction (EBSD), electrochemical tests, laser microscope and other characterization methods were used. As the heat input increased, the smoothness of the underwater cladding coating improved, with little changes in elemental distribution and phase composition. However, the content of acicular ferrite increased, while the amounts of lath bainite, lath martensite, and granular bainite decreased. As the heat input increased from 0.4 to 0.55 kJ/mm, the grain size increased from 25.3 to 55.9 μm, the proportion of low-angle grain boundaries rose from 61.3 % to 69.1 %, and the texture intensity of the (110) crystal plane increased from 16.22 to 23.83. Meanwhile, the dislocation density decreased from 4.9 × 1014 to 4.1 × 1014 m−2. These changes enhanced the corrosion resistance of underwater coating. As the heat input increased from 0.4 to 0.55 kJ/mm, the corrosion current density decreased from 2.13 × 10−5 to 3.35 × 10−6 A/cm2, and the corrosion potential increased from −0.823 to −0.529 V. Additionally, the depth-to-width ratio of the corrosion pits decreased from 0.255 to 0.053. This study laid the foundation for high-quality in-situ underwater repairs of ships and submarines made of high-strength steel.

Effect of Vibration Pretreatment-Microwave Curing Process Parameters on the Mechanical Performance of Resin-Based Composites.

The vibration pretreatment-microwave curing process can achieve high-quality molding under low-pressure conditions and is widely used in the curing of resin-based composites. This study investigated the effects of the vibration pretreatment process parameters on the void content and the fiber weight fraction of T700/TRE231; specifically, their influence on the interlaminar shear strength and impact strength of the composite. Initially, an orthogonal experimental design was employed with interlaminar shear strength as the optimization target, where vibration acceleration was determined as the primary factor and dwell time as the secondary factor. Concurrently, thermogravimetric analysis (TGA) was performed based on process parameters that corresponded to the extremum of interlaminar shear strength, revealing a 2.17% difference in fiber weight fraction among specimens with varying parameters, indicating a minimal effect of fiber weight fraction on mechanical properties. Optical digital microscope (ODM) analysis identified interlaminar large-size voids in specimens treated with vibration energy of 5 g and 15 g, while specimens subjected to a vibration energy of 10 g exhibited numerous small-sized voids within layers, suggesting that vibration acceleration influences void escape pathways. Finally, impact testing revealed the effect of the vibration pretreatment process parameters on the impact strength, implying a positive correlation between interlaminar shear strength and impact strength.

Suitability Study of Optical Coordinate Measuring Machine for Quality Assessment and Wear Phenomena Identification of Blade Edge and Surface of Planer Technical Knives.

This article discusses a comparative analysis of the wear and quality of planer knife blades used in wood planers. The novelty in this work is the use of a simple coordinate measuring machine with a vision system to assess the wear of the cutting edges of planer knives. The primary objective of the research described in this paper was to verify whether the wear of the cutting edge of planer knives can be measured quickly and accurately using an optical coordinate measuring machine with a vision system. To date, contact profilometry methods have been used for this purpose, which require a specialist apparatus and qualified measuring equipment operators and are expensive and time-consuming. The research presented in this work was conducted on twelve planer knives. The condition and wear of the working surfaces of the tested knives were assessed using an optical digital microscope. The wear of the cutting edge of the knives was measured using two methods: the contact profilometry method and an optical coordinate measuring machine equipped with a vision system. The edge profiles and their parameters obtained by the optical method were compared to the results of measurements with a stylus profilometer. Based on the research and analyses conducted, it was found that the optical method used in this research significantly shortens the time of measuring the wear of the cutting edges of planer knives. In addition, this method has a wider measurement range, and the obtained measurement results are characterized by lower measurement uncertainty.

(Invited) Novel Design of Low-Loaded Membrane Electrode Assemblies for Advanced Low-Temperature Water Electrolyzers

Development of advanced low-temperature (LT) water electrolyzers (WEs) is of crucial importance for implementation of the Hydrogen Economy. This future green economy will eliminate the greenhouse gas emissions and stop the imminent global warming and climate change. “Green” hydrogen can be produced at large scale by integration of WEs with renewable energy sources. Currently, the low-temperature proton exchange membrane (PEM) and anion exchange membrane (AEM) WEs are considered to be the most advanced WEs that can be integrated with solar panels and wind turbines to produce large quantities of green H2. The main challenges that the state-of-the-art membrane electrode assemblies (MEAs) for LTWEs are currently facing are: (i) high cost because of the high platinum group metals (PGM) loadings in their catalysts layers; (ii) limited durability caused by the instability of the catalysts and the other cell components, and (iii) safety concerns associated with the hydrogen gas crossover and the absence of technologies that can effectively keep it below the safety level of the lower flammability limit (LFL) [1, 2, 3].This work is aimed on designing of novel MEAs for LTWEs with dramatically reduced catalysts loadings, enhanced durability, and improved H2 crossover capabilities. Reactive Spray Deposition Technology (RSDT) is used as an innovative methodology for designing of advanced catalysts, catalyst and recombination layers, and MEAs for LTWEs. The RSDT is a flame assisted method [4, 5] that combines the catalysts synthesis and deposition directly on the membrane in one-step, which results in fast and facile fabrication of large scale (up to 1000 cm2) MEAs for application in LT fuel cells and water electrolyzers [5, 6]. As fabricated MEAs with ultra-low PGM catalysts loadings are tested at operating conditions typical for industrial PEM hydrogen production systems, and performance of 1.8 V at 3 A/cm2 is achieved. The MEAs of interest are tested for over 1000 hrs at steady-state conditions at 3 A/cm2. Comprehensive post-test characterization is performed by using high-resolution TEM, STEM, EDS, SEM, ICP, XRF, XCT, and digital optical microscopy and the governing degradation mechanisms are identified and discussed in detail. The impact of the design of low-loaded MEAs for LTWEs on their performance and durability is discussed in detail and their potential to meet and surpass the DOE 2030 targets is demonstrated.References https://www.energy.gov/sites/prod/files/2017/05/f34/fcto_myrdd_fuel_cells.pdf https://www.energy.gov/sites/prod/files/2015/06/f23/fcto_myrdd_production.pdfKlose, P. Trinke, T. Böhm, B. Bensmann, S. Vierrath, R. Hanke-Rauschenbach, and S. Thiele, J. Electrochem. Soc., 165, F1271–F1277 (2018).Kim, S., Myles, Maric, R., et al. Electrochimica Acta, 177, 190-200 (2015).Yu, H., Baricci, A., Bisello, A., Bonville, L., Maric, R., et al. Electrochimica Acta, 247, 1155-1168 (2017).Mirshekari, G., Ouimet, R., Zeng, Z, Yu, H., Bliznakov, S., Bonville, L., Niedzwiecki, A., Errico, S., Capuano, C., Mani, P., Ayers, K., Maric, R. International Journal for Hydrogen Energy, 46(2), 2021, pp. 1526-1539 (2021).

Titanium-Titanium Junctions in the Knee Corrode, Generating Damage Similar to the Hip

BackgroundPrevious studies identified corrosion between the modular tibial components of total knee arthroplasty devices. However, gaps persist. Compared to the hip, damage modes that occur within taper junctions in the knee remain poorly understood. In this study, we investigated corrosion on total knee arthroplasty components with titanium-titanium junctions. We asked the following question: under typical in vivo cyclic loading conditions, will the same alloy damage modes from total knee arthroplasty devices resemble those documented in the hip? MethodsA total of 50 paired titanium alloy tibial baseplates and stems were collected and semiquantitatively analyzed using Goldberg corrosion scoring. To characterize damage, a subsection of moderately and severely corroded components was sectioned and imaged using scanning electron and digital optical microscopy. ResultsOf the 100 device components, 95% showed visual evidence of corrosion. The initial contact area between the stem and bore generally occurred 3 mm from the stem taper base. Scanning electron microscopy revealed 4 damage modes, including oxide film formation, crevice corrosion, selective dissolution, and pitting. ConclusionsEach of the damage modes identified in modular titanium-titanium tibial junctions was previously reported by total hip arthroplasty retrieval studies. Cumulatively, our results suggest that mechanically assisted crevice corrosion promoted this damage in vivo.

Byzantine wall paintings from San Marco d’Alunzio, Sicily: non-invasive diagnostics and microanalytical investigation of pigments and plasters

A diagnostic investigation was carried out on twelfth century Byzantine wall paintings preserved in the Museum of Byzantine and Norman Culture and Figurative Arts of San Marco d’Alunzio (Messina, Italy) on the occasion of recent restoration works. First, the wall paintings were analyzed using portable X-Ray Fluorescence (p-XRF) and Fiber Optics Reflectance Spectroscopy (FORS) to obtain a non-invasive preliminary identification of the original palette. Then, five fragments were sampled for a micro-stratigraphy study using Digital Optical Microscope (DOM), Polarizing Optical Microscope (POM), and Scanning Electron Microscopy (SEM) combined with Energy Dispersive X-ray Spectrometry (EDS) to characterize the mortars and the blue and black pigments non unequivocally identified through non-invasive techniques. The palette included mainly earthen pigments like red and yellow ochres, green earth, and more valuable lapis lazuli blue applied on a bone black layer; while the analysis of mortars found on the different apses showed the same manufacturing technique and constitutive materials: lime-based binder with the addition of quartz, and rare calcareous lithic fragments as aggregate. The obtained results shed light on the pictorial technique used for the wall paintings and allowed us to compare the Sicilian pictorial cycle with the coeval Byzantine wall paintings preserved in Sardinia and Southern Italy.

Structural Analysis of Some Pottery Fragments Belonging to Hamangia (Phase III) Culture

Abstract The paper presents a structural analysis of two pottery fragments belonging to the Hamangia phase III Ceamurlia culture, discovered in a settlement with several living levels on the northern shore of Lake Techirghiol, at the Minerva – Paloda Hill. From two ceramic fragments, fired in a reducing atmosphere, samples were taken to perform X-ray diffraction (XRD) and wavelength‐dispersive X-ray fluorescence spectra (WDXRF) analyzes to determine the crystalline structure and composition of the ceramic materials. Digital optical microscopy was used to observe the details of the fracture surfaces of these ceramic fragments. This work contributes to the knowledge of the techniques and materials used by the Hamangia civilization in the manufacture of ceramic vessels.

Beyond Scanning Electron Microscopy: Comprehensive Pore Analysis in Transparent Ceramics Using Optical Microscopy

Developing an effective method of quantifying defects in the bulk of transparent ceramics is a challenging task that could facilitate their widespread use as a substitute for single crystals. Conventionally, SEM analysis is used to examine the microstructure but it is limited to the material surface. On the other hand, optical transmittance assesses material quality, but does not provide information on the size and concentration of defects. In this study, we illustrate the use of a digital optical microscope for the non-destructive, precise, and rapid analysis of residual porosity in transparent ceramics. YAG-based ceramics doped with Yb have been selected for this study because they are used as laser gain media, an application that requires virtually defect-free components. Different production processes were used to produce YAG samples, and the digital optical microscope analysis was used to compare them. This analysis was shown to be effective and precise to measure the size and concentration of the residual pores. In addition, the comparison of samples obtained with different production processes showed that the size and distribution of the residual porosity is affected by the drying step of the powders before shaping by pressing, as well as by the sintering aids used to ease the densification. It also showed that the transmittance is influenced by both the total volume and the concentration of the pores.

Overprinting of TPU onto PA6 Substrates: The Influences of the Interfacial Area, Surface Roughness and Processing Parameters on the Adhesion between Components.

The hybridisation of injection moulding (IM) and additive manufacturing (AM) offers the opportunity to combine the high productivity of IM and the high flexibility of AM into a single process. IM parts can be overprinted through fused filament fabrication (FFF) to allow for the customisation of parts or to add new functionalities. However, the right material pair must be chosen, and processing parameters must be optimised to achieve suitable adhesion between the components. The present study dealt with the investigation of the influence of the interfacial area, substrate surface roughness and overprinting processing parameters on the adhesion between the polyamide 6 (PA6) substrate and thermoplastic polyurethane (TPU) rib overprinted via FFF. PA6 substrates were produced through the IM of plates into a mould with different textures to obtain substrates with three different surface roughnesses. The ribs with varied interfacial areas were overprinted onto produced substrates using a desktop FFF 3D printer. To study the effect of overprinting processing parameters, the ribs were overprinted under varying printing and substrate temperatures and printing speeds according to the Box-Behnken design of experiments (DoE). The chemical composition and thermal properties of used materials were determined via attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The surface properties of prepared substrates were studied via digital optical microscopy (OM), through surface roughness measurements using a confocal microscope, through contact angle (CA) measurements and through the determination of free surface energy (SFE). The adhesion between the components was determined by evaluating the tear-off strength using a universal testing machine (UTM). With an increasing interfacial area, the tear-off strength decreased, while substrate surface roughness had no statistically significant effect. Overprinting parameters influenced the tear-off strength in the order of printing speed > printing temperature > substrate temperature. High values of tear-off strength were found for the lowest printing speed, while there were no important differences found between the middle and upper values. With increasing printing and substrate temperatures, the tear-off strength increased linearly. The highest value of tear-off strength (0.84 MPa) was observed at a printing temperature, substrate temperature and printing speed of 250 °C, 80 °C and 2 mm/s, respectively.

Integrated Investigations of Painting Materials in the Sasanian City of Ardaxšīr Khwarrah, near Firuzabad (Southern Iran)

Ancient Ardaxšīr Khwarrah, today known as Shahr-e Gur, situated near the modern town of Firuzabad in Fars, Iran, holds historical significance as the inaugural capital city of the Sasanian Empire. During archaeological excavations conducted in 2005 by an Iranian–German team directed by Mas‘oud Azarnoush and Dietrich Huff, a mud-brick complex was uncovered, revealing a remarkably well-preserved stretch of wall painting and a polychrome painted floor. The discovery prompted the hypothesis of a potential funerary context dating back to the Sasanian period. Both the wall painting and painted floor have suffered extensive deterioration attributed to the environmental conditions of the archaeological site, which was inscribed on the UNESCO World Heritage List in 2020. To address the urgent need for preservation and further understanding of the site’s artistic and structural elements, an emergency diagnostic project was initiated. Non-invasive investigations were carried out on the wall and floor by optical digital microscopy and portable energy-dispersive X-ray fluorescence. Additionally, representative minute samples underwent analysis through various techniques, including micro-X-ray fluorescence, polarised light microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, micro-Raman spectroscopy, micro-Fourier Transform Infrared Spectroscopy, gas chromatography-mass spectrometry and pyrolysis coupled with gas chromatography-mass spectrometry. The palette of the floor and mural paintings were identified to contain red and yellow ochres, lead-based pigments, carbon black and bone white. The unexpected presence of Egyptian blue mixed with green earth was recognised in the green hues of the wall painting. The detection of protein material in both the wall painting and polychrome floor indicates the use of “a secco” technique, thereby shedding light on the artistic practices employed in Ardaxšīr Khwarrah.

Influence of Bioceramic Cements on the Quality of Obturation of the Immature Tooth: An In Vitro Microscopic and Tomographic Study.

The present in vitro study focuses on the filling ability of three different bioceramic cements with or without the addition of a bioceramic sealer in an open apex model on the marginal apical adaptation, tubule infiltrations, and void distributions as well as the interface between the cement and the sealer materials. To this end, sixty mandibular premolars were used. MTA-Biorep (BR), Biodentine (BD), and Well-Root Putty (WR) were used to obturate the open apex model with or without the addition of a bioceramic sealer, namely TotalFill® BC sealer™ (TF). A digital optical microscope and scanning electron microscope (SEM) were used to investigate the cement-dentin interface, marginal apical adaptation, and the material infiltration into the dentinal tubules. Micro-computed X-ray tomography and digital optical microscopy were used to investigate the cement-sealer interface. The results were analyzed by using the Kruskal-Wallis test. No significant difference was found between the groups for the marginal apical adaptation quality (p > 0.05). Good adaptation of the dentin-cement interface was found for all tested groups and the sealer was placed between the cement material and dentinal walls. All the groups demonstrated some infiltrations into the dentinal tubules at the coronal part except for the BR group. A good internal interface was found between the cement and the sealer with the presence of voids at the external interface. A larger number of voids were found in the case of the BD-TF group compared to each of the other two groups (p < 0.05). Within the limitations of the present in vitro study, all the groups demonstrated good marginal apical adaptation. The use of a sealer in an open apex does not guarantee good filling and, in addition, creates voids at the external interfaces with the dental walls when the premixed sealer is used with powder-liquid cement systems. The use of a premixed bioceramic cement could offer fewer complications than when a powder-liquid cement system is used.

Peanut shaped auxetic cementitious cellular composite (ACCC)

Auxetic cementitious cellular composites (ACCCs) exhibit desirable mechanical properties (e.g., high fracture resistance and energy dissipation), due to their unique deformation characteristics. In this study, a new type of cementitious auxetic material, referred to as peanut shaped ACCC, has been designed and subsequently architected using additive manufacturing techniques. Two peanut shaped ACCCs specimens with different pseudo-minor axes have been tested under uniaxial compression with Digital Image Correlation (DIC) to assess their compressive behavior, peak strength, Poisson’s ratio, and energy dissipation capacity. Additionally, cyclic tests were conducted to investigate their compressive resilience properties, further elucidated through microstructural analysis using a digital optical microscope. The mechanical test results were also compared with those of previously developed elliptical-shaped ACCCs. Furthermore, a numerical model was used to simulate the mechanical behavior of peanut shaped ACCCs under uniaxial compression, and showed a good agreement with the experimental data. The auxetic behavior observed in peanut shaped ACCCs arises from the rotation of sections facilitated by fiber bridging at the ligament of adjacent holes within the cementitious unit cell. In comparison to elliptical-shaped ACCCs, peanut shaped ACCCs can exhibit a slightly more negative Poisson's ratio and mitigate stress concentration. The reduction of stress concentration enables peanut shaped ACCCs to dissipate substantial energy, showcasing enhanced ductility and toughness. In cyclic tests, peanut shaped ACCCs exhibit superior recoverable deformation elasticity, attributed to robust fiber bridging capacity. The exceptional mechanical properties exhibited by peanut shaped ACCCs offer a scalable solution for developing energy-absorbent and multifunctional cementitious materials for smart infrastructure.

Influence of pulse duration on the fatigue behavior of a carbon‐fiber‐reinforced composite under cyclic three‐point bending at 20 kHz

AbstractVery high cycle fatigue (VHCF) experiments are limited in practice due to their long testing times. In ultrasonic fatigue test (UFT) systems, the cyclic oscillation is applied using resonance at 20 kHz with a pulse and pause sequence. However, determining optimal pulse durations to achieve minimal testing time and avoid thermal‐induced fatigue damage in fiber‐reinforced polymer composites remains a challenge. In this work, several fatigue experiments, temperature analyses, and digital light optical microscopy were carried out to evaluate the influence of pulse duration on the fatigue behavior of a carbon‐fiber fabric reinforced in polyether‐ketone‐ketone (CF‐PEKK) composite. A shorter pulse duration with the same pulse–pause ratio as the longer pulse duration is proposed for higher stress amplitudes to avoid any thermal influence during mechanical fatigue without altering the underlying fatigue damage mechanisms.

Microstructure and Mechanical Properties of Ti6Al4V to Al2O3 Brazed Joints Using Ti-Ag/Cu-Ti Thin Films

The processing and characterizing of bonding Ti6Al4V to Al2O3 brazed joints using interlayer thin films was investigated. The brazing was conducted in a tubular furnace with an argon flux at 980 °C for 30 min. The brazing fillers consisted of different combinations of thin Ag/Cu and Ti films with variable thicknesses. The joint interface analysis involved using digital microscopy (DM) and optical microscopy (OM). Microstructural characterization and chemical composition were performed via scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Mechanical properties were assessed through microhardness and shear strength tests. Brazing successfully produced interfaces with a combination of titanium films and Ag/Cu as brazing filler. The results revealed that the interface mainly comprises Ti2Cu, TiCu2Al, α-Ti, and Ti2(Cu,Ag). Some segregation of (Ag) was observed at the interfaces, but a decrease in its amount was observed when compared to joints produced using Ag/Cu fillers. The thickness of the titanium film in the brazing filler strongly influenced the integrity of the joints. The amount of (Ag) at the interface diminished as the Ti film’s thickness decreased, leading to an improvement in the mechanical properties of the joints. Using a combination of Ag/Cu and Ti thin films revealed a potential approach to reduce the segregation of soft phases at interfaces, promoting a significant improvement in joining metal to ceramic materials.

A Tubular-Mounted Digital Camera Versus Optical Surgical Microscope for Minimally Invasive Lumbar Decompression Surgery: The Impact on Operative Times, Ergonomics, and Workflow

ObjectivesUnderstanding the ergonomic impact is foundational to critically evaluate the value and safety of enabling technologies in spinal Minimally Invasive Spine Surgeries (MISS). This study assessed the impact of tube-mounted digital camera (TMDC) vs. optical surgical microscope (OSM) in single-level MISS on operative times, durotomy rate, surgeon ergonomics, safety, and operating room workflow. MethodsIn a retrospective study, we compared consecutive single-level MIS lumbar decompression surgeries with TMDC (Sep 2021-Jun 2022) to a historical OSM cohort (Jan 2020-Jul 2021). Data included patient demographics, operative times, durotomy incidence, surgeon ergonomics (REBA scores), and equipment impact via staff surveys. T-tests assessed operative times, while Pearson chi-squared tests compared sex. Age, BMI, and CCI comparisons used Wilcoxon rank-sum tests, and survey results were analyzed with Wilcoxon signed-rank tests. ResultsIn total, 74 and 82 patients were included in the TMDC and OSM groups, respectively. Age, sex, and CCI did not significantly differ between both groups. The TMDC group had a higher BMI (29. 6 ± 5.1) versus the OSM group (29.0 ± 7.5) (p=0.04). The TMDC group (n=74) had significantly shorter operative times (57.3±16.6 minutes) compared to the OSM group (n=82) (66.7±22.5 minutes) (p=0.004), with no difference in durotomy rates (p=0.42). TMDC use yielded lower REBA scores (3) vs. OSM (4.1±0.77) (p<0.001). Surveys indicated improved safety, setup time, and workflow with TMDC (p<0.001). ConclusionsTMDC in single-level MIS lumbar decompression surgery improved surgeon ergonomics, reduced operative times, and maintained durotomy rates, enhancing operative room efficiency. Evaluating technology's ergonomic impact is vital for safety and value assessment.

Spatiotemporal mapping of nanotopography and thickness transitions of ultrathin foam films.

Freshly formed soap films, soap bubbles, or foam films display iridescent colors due to thin film interference that changes as squeeze flow drives drainage and a progressive decrease in film thickness. Ultrathin (thickness <100 nm) freestanding films of soft matter containing micelles, particles, polyelectrolyte-surfactant complexes, or other supramolecular structures or liquid crystalline phases display drainage via stratification. A fascinating array of thickness variations and transitions, including stepwise thinning and coexistence of thick-thin flat regions, arise in micellar foam films that undergo drainage via stratification. In this tutorial, we describe the IDIOM (interferometry digital imaging optical microscopy) protocols that combine the conventional interferometry principle with digital filtration and image analysis to obtain nanometer accuracy for thickness determination while having high spatial and temporal resolution. We provide fully executable image analysis codes and algorithms for the analysis of nanotopography and summarize some of the unique insights obtained for stratified micellar foam films.

Mechanical Properties of the Carbonized Layer Formed by Ion Flow Orientated at Different Angles to the Polyurethane Surface.

Polymer materials are widely used in medicine due to their mechanical properties and biological inertness. When ion-plasma treatment is used on a polymer material, a carbonization process occurs in the surface nanolayer of the polymer sample. As a result, a surface carbonized nanolayer is formed, which has mechanical properties different from those of the substrate. This layer has good biocompatibility. The formation of a carbonized nanolayer on the surface of polymer implants makes it possible to reduce the body's reaction to a foreign body. Typically, to study the properties of a carbonized layer, flat polymer samples are used, which are treated with an ion flow perpendicular to the surface. But medical endoprostheses often have a curved surface, so ion-plasma treatment can occur at different angles to the surface. This paper presents the results of a study of the morphological and mechanical properties of a carbonized layer formed on a polyurethane surface. The dependence of these properties on the directional angle of the ion flow and its fluence has been established. To study the surface morphology and elastic properties, methods of atomic force microscopy and methods of elasticity theory were used. The strength properties of the carbonized layer were studied using a stretching device combined with a digital optical microscope.

Crack resistance of carbonized layer of multilayer polyurethane with nanofillers. Combination of casting, solution, carbonization by ion implantation technologies

The paper describes the results of an experimental study of a polyurethane material treated by ion implantation technology. The problems of crack growth in the near-surface layer carbonized by ion treatment were investigated using digital optical microscopy. The methods of atomic force microscopy allowed studying the possibility of carbonized layers delamination from the substrate. As a result, the technology for the production of a multilayer polyurethane material with nanofillers (nanotubes, nanodiamonds, fullerenes, graphenes) and its optimal modification by ion implantation treatment was developed, which makes it possible to improve the biocompatibility of polyurethane implants with human tissues.