Assessment Of Surface Damage Research Articles

Assessment of whole cartilage surface damage in an osteoarthritis rat model: The Cartilage Roughness Score (CRS) utilizing microcomputed tomography

ObjectiveThis study aims to establish an accurate and robust imaging biomarker for pre-clinical osteoarthritis (OA) research, focusing on early detection of cartilage surface degeneration. MethodUsing 50 male Wistar rats, this study aims to observe Collagenase Induced Osteoarthritis (CIOA) progression through microcomputed x-ray tomography (µCT), histopathological analysis, and gait analysis. A novel parameter, Cartilage Roughness Score (CRS), was developed for assessing cartilage structural damage from µCT data and was compared with histological OARSI Cartilage Degeneration Score (OARSI CDS). Additionally, as CRS maps the full surface, it was used to simulate the level of uncertainty in histological sampling. ResultsCRS and OARSI CDS have a linear relationship. CRS for healthy cartilage is 2.75 (95% CI: 1.14-4.36) and with every 1 unit increase in OARSI, CRS is expected to increase by 0.64 (95% CI: 0.35-0.92). Cartilage degeneration due to CIOA was evident in both histopathological scoring and CRS. However, only CRS was sensitive enough to show consistent damage progression from day 10 to day 60. Furthermore, our simulation for histological sampling suggested that up to 16 coronal slices with 200µm spacing would be needed to accurately represent the full extent of cartilage surface degeneration in a slice wise manner. Gait analysis showed changes solely at eight days post-collagenase injection, normalizing by day 60. ConclusionThe CRS analysis method emerges as a robust tool for cartilage surface damage assessment. This study demonstrates the potential of automatic 3D analysis over the traditional 2D histological approach when evaluating cartilage surface damage. Data statementMicro-computed tomography data is available via ida.fairdata.fi46 (https://doi.org/10.23729/f33d3ba8-01b8-47af-90dd-94b7c7861247)

Association between dry eye disease subtypes and rheumatoid arthritis

Aim of the workTo evaluate the association of dry eye disease (DED) subtypes (aqueous deficient dry eye, ADDE and evaporative dry eye, EDE) and the presence of rheumatoid arthritis (RA) in patients. Patients and methods260 volunteer DED participants were recruited for an observational cross-sectional study based on the Tear Film Ocular Society Dry Eye Workshop II criteria, which included tear film osmolarity, fluorescence break-up time, and ocular surface damage assessment. Participants were recruited using QR linked to designated mobile forms to obtain symptomatology status, demographics, and RA diagnosis by their medical doctor. Tear meniscus and lipid layer were also evaluated to differentiate between ADDE, EDE, or mixed dry eye in addition to the DED diagnostic criteria. Participants with mixed dry eye were excluded from the analysis to avoid bias. ResultsAfter initial recruitment, 149 eligible participants with an ADDE or EDE diagnosis were included in the final analysis, where 12,1% have an RA diagnosis. The ADDE group had a higher likelihood of having RA (OR = 4.69, 95 %CI = 1.46–15.01) than the EDE group. Additionally, the number of participants with RA in the ADDE group was statistically higher than those in the EDE group (all p = 0.006). Furthermore, a correlation was obtained between RA and a diagnosis of ADDE (p = 0.005). ConclusionThere was a significant association between ADDE and the presence of RA in patients and the association was more likely compared to those with EDE. This finding underscores the need for specific diagnostic and management strategies for RA patients presenting with DED.

Bridge deck surface damage assessment using point cloud data

Bridge deck condition assessments are typically conducted through visual inspections and by incorporating traditional contact sensors for Non-Destructive Evaluation techniques such as hammer sounding and chain dragging, which require the keen expertise of trained inspectors. The accuracy of these inspections is proportional to the level of deterioration of the bridge deck, as the ability of the inspectors is correlated to the apparent level of damage. This study aims to improve the accuracy of bridge deck inspection processes by utilizing non-destructive evaluation techniques, including analyzing point cloud data gathered via Light Detection and Ranging (LiDAR) as a geometry-capturing tool for identifying surface irregularities. This research aims to evaluate and quantify the effectiveness and efficiency of LiDAR sensors in contributing to the suite of technologies available to perform bridge deck condition assessment. To achieve this, the research proposes to understand the deterioration pattern of New Jersey bridges, evaluate the results gathered from point cloud data collected on a full-scale bridge deck, and quantify the information gained from deploying LiDAR on operating bridges in New Jersey. Two data processing approaches were chosen to measure the gross and fine dimensions of the evaluated bridge decks, such as the Curvature Extraction and Slope Analysis method, and the Least Square Plane Fitting method, resulting in an accuracy of 97.92% in reference to the results gathered from reports generated through the analysis of state-of-the-art NDE technology data and visual inspection.

A simplified method for risk assessment of surface damage of marine reinforced concrete structures

For marine reinforced concrete (RC) structures under chloride-attack, the risks of member surface damage can be evaluated using random field analysis method, considering the spatial variations of durability parameters. However, the random field analysis method requires high computational cost and advanced skills, and is not feasible for engineering practice. Recognizing this difficulty, a simplified method is proposed in this paper based on the statistical characteristics of time to corrosion initiation and surface damage. The new method establishes the mappings between the probabilities of member surface damage and the probability (or reliability index) of corrosion initiation at the same age. Thus, engineers and decision-makers can estimate the risk of surface damage through reliability index of corrosion initiation, with the latter can be obtained relatively easily. Probabilistic analysis for the durability performance of a RC slab serviced in marine environment is performed to demonstrate the method. The accuracy of the proposed method is examined through the comparison with the random field simulation method and experimental results in literature.

Hyperbolic Secant Subsidence Prediction Model under Thick Loose Layer Mining Area

In China, as a major resource, coal has made great contributions to national energy security and social development. The mining of coal resources can cause surface subsidence damage, and in particular, the mining of coal resources in thick loose layer mines is the most serious. How to accurately predict the surface subsidence caused by coal mining in thick loose layer mines has become an urgent problem to be solved. To solve this problem, numerical simulations based on the measured data were used to reveal that the thickness of the loose layer is the intrinsic mechanism that affects the value of the surface subsidence and the large range of subsidence. On this basis, the hyperbolic secant function is used as the influence function of unit mining to derive the expected model of subsidence under thick loose layer conditions: the hyperbolic secant subsidence prediction model. Compared with the probability integral method, the hyperbolic secant subsidence prediction model’s prediction accuracy RMSE value is improved by 38%. The hyperbolic secant subsidence prediction model can realize accurate estimation of the subsidence value in the thick loose layer mine area. This greatly enriches the mining subsidence prediction theory and provides a scientific basis for the assessment of surface damage and ecological environment restoration after coal seam mining under a thick loose seam mining area.

Surface damage assessment by analysis of electrical resistance changes in graphite-based sensing skin

Surface damage assessment by analysis of electrical resistance changes in graphite-based sensing skin

Backside wear in total knee replacement: A new quantitative measurement method and a comparison of polished cobalt-chromium tibial trays with titanium tibial trays

Abstract

X-ray characterization technique for the assessment of surface damage in GaN wafers

SixPoint Materials has successfully switched to production of two-inch diameter GaN wafers using the ammonothermal method. Crystal quality values are high with dislocation densities typically in the low 105 cm−2. In efforts to produce true epi-ready material, investigations were made to develop a technique to study surface damage caused by the back-end process using X-ray diffraction methods. Analysis of peak tailing from X-ray rocking curves of the (1 1 4) reflection indicates the progression of surface damage during each step of the back-end process. For instance, the tailing can be partially represented using full width five thousand max (FW5000M) values. By using a peak with a low glancing angle, such as the (1 1 4) reflection’s angle of 10.8662°, more of the X-ray beam is scattered in the surface region, providing an improved measurement of surface damage. Since this technique is non-destructive and can be performed without dismounting the sample from its ceramic back-end processing plate, it can provide information on the damaged layer at each stage of the back-end process. Using this technique to evaluate samples from various manufacturers, we found a lack of uniformity in surface damage from GaN companies. It is our hope that this technique will be adopted to better standardize surface damage measurements in the GaN field.

Effect of tempera paint composition on their superficial physical properties- application of interferometric profilometry and hyperspectral imaging techniques

Abstract Interferometric profilometry and hyperspectral imaging techniques combined with traditional analytical techniques such as spectrophotometry, stereomicroscopy, X-ray diffraction, scanning electron microscopy, particle size analysis, and thermogravimetry were used to characterize tempera paint mock-ups. These paint mock-ups were prepared as binary mixtures made by mixing either egg yolk or rabbit glue binders with one of ten pigments traditionally used by mediaeval artists, namely lime, calcium sulfate, white lead, minium, hematite, cinnabar, azurite, lapis lazuli, blue smalt and malachite. We evaluated the effects of mineralogical composition, pigment particle size and morphology, as well as the type and concentration of the binder on the physical properties of the paintś surface. Results showed that all the above compositional aspects had a direct influence on the paintś color, reflectance, and roughness. Moreover, mineral impurities and neoformed minerals due to pigment-binder interaction during paint preparation had a crucial effect on the superficial physical properties of paints. The analytical results proved the usefulness of interferometric profilometry and hyperspectral imaging techniques for the characterization of paint surfaces. The gained information will help conservation specialists in the evaluation of the impact of conservation treatments on the paint surface and the assessment of surface damage caused by weathering processes.

Surface Profiling and Core Evaluation of Aluminum Honeycomb Sandwich Aircraft Panels Using Multi-Frequency Eddy Current Testing.

Surface damage on honeycomb aircraft panels is often measured manually, and is therefore subject to variation based on inspection personnel. Eddy current testing (ECT) is sensitive to variations in probe-to-specimen spacing, or lift-off, and is thus promising for high-resolution profiling of surface damage on aluminum panels. Lower frequency testing also allows inspection through the face sheet, an advantage over optical 3D scanning methods. This paper presents results from the ECT inspection of surface damage on an approximately flat aluminum honeycomb aircraft panel, and compares the measurements to those taken using optical 3D scanning technology. An ECT C-Scan of the dented panel surface was obtained by attaching the probe to a robotic scanning apparatus. Data was taken simultaneously at four frequencies of 25, 100, 400 and 1600 kHz. A reference surface was then defined that approximated the original, undamaged panel surface, which also compensated for the effects of specimen tilt and thermal drift within the ECT instrument. Data was converted to lift-off using height calibration curves developed for each probe frequency. A damage region of 22,550 mm2 area with dents ranging in depth from 0.13–1.01 mm was analyzed. The method was accurate at 1600 kHz to within 0.05 mm (2σ) when compared with 231 measurements taken via optical 3D scanning. Testing at 25 kHz revealed a 3.2 mm cell size within the honeycomb core, which was confirmed via destructive evaluation. As a result, ECT demonstrates potential for implementation as a method for rapid in-field aircraft panel surface damage assessment.

Noninvasive surface damage assessment of bovine articular cartilage explants by reflected polarized light microscopy.

Articular surface damage is a hallmark of cartilage degeneration. Noninvasive assessment of cartilage microstructural alterations has potential clinical value. In this study, we use bovine patellofemoral articular cartilage explants treated with mechanical scraping and collagenase to create cartilage surface disruption, and use polarized reflectance microscopy to quantify alterations to surface and sub-surface microstructure. Reflected polarized signal was sensitive to mild damage to the cartilage surface, and highlighted disruptive alterations. The results indicate the efficacy of reflected polarized light microscopy in assessing the microstructural status of superficial articular cartilage.

Surface crack density and recast layer thickness analysis in WEDM process through response surface methodology

ABSTRACTIn this work, quantitative assessment of surface damage in terms of parameters like surface crack density and recast layer thickness in wire electrical discharge machining (WEDM) process has been undertaken. The effect of processing conditions on crack formation is studied using scanning electron microscope. Surface crack density and recast layer thickness analysis in terms of machining parameters such as pulse on time, pulse off time, peak current, spark gap voltage significantly deteriorate the microstructure of machined samples, which produces the deeper, wider overlapping craters, pock marks, globules of debris and micro cracks. The microstructure analysis of WEDM surface was based upon the theory of electrical discharge phase and metallurgical physics. It is found that the pulse on time, pulse off time and peak current are the most dominating parameters for both surface crack density and recast layer thickness.

An experimental procedure for surface damage assessment in railway wheel and rail steels

The assessment of damage in rail–wheel cyclic contact requires considering the combined action of different damage mechanisms, such as wear, ratcheting, surface or subsurface crack nucleation and propagation. Models, usually requiring experimental calibration, are available for assessing these phenomena. The best way to calibrate them is based on cyclic contact tests, as these represent the real working conditions more closely. However, some experimental information, such as microstructural changes or crack paths, can be obtained only by destructive methods at the end of the tests, and their evolution cannot be monitored; other parameters, such as the wear rate, can only be determined during time consuming breaks to the tests. In this work, non destructive measurements of vibrations, torque and Barkhausen noise were introduced as indicators of damage evolution in cyclic contact tests on a high performance steel for railway wheels, coupled with a rail steel. In particular, their correlation with surface state, wear rate, subsurface microstructure and presence of cracks was shown.

Clinical failure analysis of contemporary ceramic-on-ceramic total hip replacements

The present study investigates the performance of ceramic-on-ceramic total hip replacements by combining a retrieval analysis with a survivorship analysis to elucidate mechanisms that led to clinical failure. Semiquantitative surface damage assessment, contact profilometry, contour measurements, and scanning electron microscopy were performed to characterize the types and quantify the extent of surface damage on the retrieved ceramic components. The implantation period was positively correlated with both damage scores of the femoral heads (R = 0.573, p < 0.001) and the acetabular cups (R = 0.592, p < 0.001). Increased maximal out-of-roundness values of the femoral heads correlated with both increased metal transfer damage score (R = 0.384, p = 0.023) and increased stripe damage score (R = 0.729, p ≤ 0.001) of the acetabular liners. The damage rate (damage score/year) for both the retrieved heads and acetabular liners was at least 2.2-fold greater at inclination angles of >45° than the damage rate at inclination angles of ≤45°. For the retrieved femoral heads only, the linear wear rate of 25.5 ± 21.3 µm/year at inclination angles of >45° was 6-fold greater than the linear wear rate of 4.2 ± 2.3 µm/year at inclination angles of ≤45°. Metal transfer on the ceramic bearing surface could possibly contribute to fluid-film starvation and, in combination with an increased inclination angle, may facilitate an adhesive wear mechanism associated with stripe surface damage. At our institution, the clinical survivorship of ceramic-on-ceramic total hip replacements was 98.9% (a total of 9 out of 815 patients were revised within 10 years after total hip arthroplasty) with revision as the end point, suggesting their safe use in younger patients.

X-ray characterization techniques for the assessment of surface damage in crystalline wafers: A model study in AlN

A high-resolution X-ray diffraction method with enhanced surface sensitivity has been used to investigate the effects of various polishing steps on the near-surface region of single crystal substrates. The method involves the study of a highly asymmetric reflection, observable under grazing incidence conditions. Analysis of rocking curve measurements and reciprocal space maps (RSMs) revealed subtle structural differences between the polished substrates. For aluminum nitride wafers, damage induced from diamond sawing and mechanical polishing was readily identifiable by on-axis rocking curves, but this method was unable to distinguish between sample surfaces subjected to various degrees of chemical mechanical polishing (CMP). To characterize sufficiently these surfaces, (10.3) RSMs were measured to provide both qualitative and quantitative information about the near-surface region. Two features present in the RSMs were utilized to quantitatively assess the polished wafers: the magnitude of the diffuse scatter in the omega-scans and the elongation of the crystal truncation rod. The method is able to distinguish between different degrees of CMP surface preparation and provides metrics to quantify subsurface damage after this polishing step.

Tear Film Aberration Dynamics and Vision-Related Quality of Life in Patients with Dry Eye Disease

Corneal and ocular wavefront aberrations were recorded together with clinical examination results and patient-reported vision-related quality-of-life evaluation results to define the relevance of dynamic optical analysis of the eye in dry eye disease (DED). Prospective and comparative clinical study. Forty DED patients and 40 age- and gender-matched control subjects. Serial measurements of ocular and corneal higher-order aberrations (HOAs) after blink were performed for 10 seconds using the KR-1 aberrometer (Topcon, Clichy, France). Vision-related health-targeted quality of life was evaluated using the Ocular Surface Disease Index (OSDI) questionnaire. The clinical examination included tear film assessment (tear film break-up time and Schirmer I test), ocular surface damage assessment with the Oxford and van Bijsterveld indexes, and Meibomian dysfunction grading. Tear osmolarity also was measured. The time course of HOAs and modulation transfer function (MTF) was compared between groups and was analyzed in comparison with the OSDI and clinical data in DED patients. The root mean square of ocular and corneal total HOAs, particularly third-order aberrations, significantly increased over the 10-second period in DED patients, whereas no change occurred in controls. Analysis of MTF revealed progressive degradation of ocular optical quality resulting from loss of contrast at intermediate and high spatial frequencies in DED patients compared with controls. The progression index for corneal HOAs was correlated with the subjective index of patient-reported visual outcomes and with objective clinical findings of tear film and ocular surface damage. Objective measurement of the time course of HOAs may constitute a new single instrument to evaluate and manage patients with DED because it reliably reflects the completeness of the disease.

In Vivo Oxidation Contributes to Delamination but not Pitting in Polyethylene Components for Total Knee Arthroplasty

The aim of this study was to better understand how in vivo oxidation contributes to fatigue damage in total knee arthroplasty (TKA). A total of 119 tibial inserts were consecutively collected after revision surgery. Of the 119 polyethylene retrievals, 29 were gamma sterilized in air (historical), whereas the remaining 90 were gamma sterilized in nitrogen (conventional). Surface damage assessment and characterization of oxidation were performed on all the retrievals. Delamination was significantly more prevalent and extensive in the longer-term, highly oxidized, historical tibial inserts. Pitting damage, in contrast, seemed to be equally prevalent between both retrieval groups and was not correlated with in vivo oxidation. Our findings support our hypothesis that in vivo oxidation is a contributing factor to delamination, but not pitting, in TKA. Despite the lower oxidation displayed by conventional retrievals, this study provides strong evidence that delamination secondary to in vivo oxidation may occur during the second decade of implantation.

Assessment of surface damage and sidewall implantation in AlGaN-based high electron mobility transistor devices caused during focused-ion-beam milling

The surface amorphization and ion implantation in AlGaN-based high electron mobility transistor (HEMT) model structures caused by ionized gallium during focused-ion-beam milling have been investigated. The extent of Ga+ surface implantation likely to occur during deposition of the surface Pt protective layer was simulated for 30, 5, and 2 keV ion beams. Electron-transparent cross sections of AlGaN/GaN and AlGaN/AlN/GaN HEMT structures were then prepared for electron microscope observation using a dual-beam focused-ion-beam instrument operated at different beam energies. Experimental studies revealed that the upper 9 nm of the AlGaN layer had been amorphized during Pt deposition. Nanoprobe x-ray microanalysis confirmed intermixing with Pt as well as implantation of Ga ions into the upper regions of the foil. Deposition of the first few hundred nanometers of Pt using an electron beam, rather than the usual Ga+ beam, enabled surface damage and ion implantation to be completely avoided. Sidewall damage for specially prepared cross sections was assessed from bright-field and high-angle annular-dark-field images. For final membrane thinning at 30, 5, and 2 keV, the thicknesses of visibly damaged layers were approximately 20, 8, and 4 nm, respectively, roughly twice as large as predicted by simulations.

Assessment of Surface Damage in Thermally Aged FSX414 Cobalt-Based Superalloy Using Ultrasonic Rayleigh Wave

An attempt was made to assess the surface damage in the isothermally degraded FSX414 Co-based superalloy using ultrasonic Rayleigh surface wave. Microstructural analysis (amount of solute Cr near the surface) and measurement of ultrasonic velocity and attenuation were performed after isothermal degradation heat treatment at 1100°C for up to 4000 hours. Rayleigh wave velocity was observed to increase with aging time, which was attributed to the increased depletion of Cr near the surface. Strong frequency dependence of Rayleigh wave velocity was found in the specimens with surface depletion layer. Attenuation coefficient of Rayleigh wave increased with increasing aging time. Therefore, both attenuation and velocity of ultrasonic Rayleigh wave are suggested as potential nondestructive evaluation parameters for the characterization of the thermally aged FSX414 superalloy.

Surface damage assessment of nanometre finish substrates using differential reflectance spectroscopy

Differential reflectance spectroscopy (DRS) is a comparative technique that measures the normalized difference in reflectivity between samples in the UV to near IR region of the spectrum. We apply the technique to gallium arsenide substrates that have undergone different processing treatment. Spectral features are observed that can be assigned to critical point energies of the band structure. It is suggested that these features arise from strain in the crystal lattice and that DRS is a possible candidate for monitoring process-induced damage in substrate preparation.