Three-dimensional Characterization Research Articles

Three-dimensional characterization of skyrmions

Three-dimensional characterization of skyrmions

Three-dimensional characterization of sex differences in abdominal aortic aneurysm progression via vascular deformation mapping

Although abdominal aortic aneurysms (AAA) are more common in men, women are at greater risk for AAA growth/rupture. Vascular deformation mapping (VDM) utilizes deformable image registration to qualify and quantify 3D-AAA growth using computed tomography angiograms (CTA). In this study we leveraged VDM to investigate sex differences in AAA growth patterns. Patients with infra-renal AAA and ≥ 2 CTA were identified. Males and females were matched for age, hypertension, and smoking history. Patient characteristics, maximum diameter (Dmax), and AAA volume were obtained. CTA images were segmented, and VDM was conducted to quantify 3D AAA growth rate per year (GR, cm/year). Statistical shape modeling was utilized to compute mean aneurysm shapes and 3D GR. Average GR was evaluated at specific regions of the aortic surface for males and females. Seventeen males and 17 females were matched. At the individual level, there were no sex differences in changes in Dmax or AAA volume. However, females had larger GR across the anterior and right lateral AAA (1.33 vs 0.89 and 1.56 vs 0.74 cm/year, respectively), despite no difference in posterior or left lateral AAA GR. Despite comparable changes in Dmax, AAA volume, and GR magnitude, women demonstrated a more eccentric, anterior-predominant, AAA growth pattern.

Mandibular second molar impaction: introducing a novel and validated 3D classification system

BackgroundMandibular second molar (M2M) impaction is a clinically significant manifestation of eruption disturbance in dental development. The primary aim of this study was to investigate the impact of the three-dimensional (3D) characterization on clinical and therapeutic decisions for M2M impaction. The secondary aim was to introduce a validated 3D classification system incorporating both surgical and orthodontic parameters.MethodsBidimensional (2D) and 3D radiological records of 15 impacted M2M were collected and deidentified. Ten experienced clinicians (5 oral surgeons;5 orthodontists) categorized each case, first based on 2D records and then with 3D scans. The degree of orthodontic and surgical difficulty in treating impacted M2M was evaluated using a novel classification system based on anatomical and radiological features. The primary outcome variable was the assessment of differences in diagnosis and decision-making protocol using 2D or 3D records, where clinical relevance ranged from 0 to 4. The secondary outcome variable was the validation analysis of the proposed 3D classification system to determine the concordance among the clinicians. Descriptive statistics and multivariable inferential analysis based on Akaike information criterion (AIC) were performed (α = 0.05).Results3D examination allowed a better visualization of M2M impaction with higher clinical relevance for diagnosis of M2M root relationship to alveolar nerve and lingual plate, height to alveolar crest, depth, and inclination relative to the first molar and position relative to the third molar (range:2.69–3.43). The proposed 3D classification of M2M impaction changed clinical decisions regarding surgical-orthodontic approach, biomechanics, patient education, and treatment time estimate (range:2.59–3.33). In the validation analysis of the classification, no evidence of inter- or intra-group (surgeon/orthodontist) bias in score attribution occurred: the model with the minimum AIC was the null model (AIC = 718.04).Conclusion3D evaluation of impacted M2Ms could enhance diagnostic accuracy, and a classification system was proposed and validated by a group of experienced surgeons and orthodontists with high concordance.

Three-Dimensional Characterization of Sex Differences in Abdominal Aortic Aneurysm Progression Via Vascular Deformation Mapping

Three-Dimensional Characterization of Sex Differences in Abdominal Aortic Aneurysm Progression Via Vascular Deformation Mapping

Multimodal three-dimensional characterization of murine skeletal muscle micro-scale elasticity, structure, and composition: Impact of dysferlinopathy, Duchenne muscular dystrophy, and age on three hind-limb muscles

Skeletal muscle tissue function is governed by the mechanical properties and organization of its components, including myofibers, extracellular matrix, and adipose tissue, which can be modified by the onset and progression of many disorders. This study used a novel combination of quantitative micro-elastography and clearing-enhanced three-dimensional (3D) microscopy to assess 3D micro-scale elasticity and micro-architecture of muscles from two muscular dystrophies: dysferlinopathy and Duchenne muscular dystrophy, using male BLA/J and mdx mice, respectively, and their wild-type (WT) controls. We examined three muscles with varying proportions of slow- and fast-twitch myofibers: the soleus (predominantly slow), extensor digitorum longus (EDL; fast), and quadriceps (mixed), from BLA/J and WTBLA/J mice aged 3, 10, and 24 months, and mdx and WTmdx mice aged 10 months. Both dysferlin deficiency and age reduced the elasticity and variability of elasticity of the soleus and quadriceps, but not EDL. Overall, the BLA/J soleus was 20% softer than WT and less mechanically heterogeneous (−14% in standard deviation of elasticity). The BLA/J quadriceps at 24 months was 72% softer than WT and less mechanically heterogeneous (−59% in standard deviation), with substantial adipose tissue accumulation. While mdx muscles did not differ quantitatively from WT, regional heterogeneity was evident in micro-scale elasticity and micro-architecture of quadriceps (e.g., 11.2 kPa in a region with marked pathology vs 3.8 kPa in a less affected area). These results demonstrate differing biomechanical changes in hind-limb muscles of two distinct muscular dystrophies, emphasizing the potential for this novel multimodal technique to identify important differences between various myopathies.

Three-Dimensional (3D) Nondestructive Characterization of the Spatial Distribution and Complex Properties of Polytypes on 4H-SiC Wafers

Three-Dimensional (3D) Nondestructive Characterization of the Spatial Distribution and Complex Properties of Polytypes on 4H-SiC Wafers

Now and then in eukaryotic DNA methylation.

Since the mid-1970s, increasingly innovative methods to detect DNA methylation provided detailed information about its distribution, functions, and dynamics. As a result, new concepts were formulated and older ones were revised, transforming our understanding of the associated biology and catalyzing unprecedented advances in biomedical research, drug development, anthropology, and evolutionary biology. In this review, we discuss a few of the most notable advances, which are intimately intertwined with the study of DNA methylation, with a particular emphasis on the past three decades. Examples of these strides include elucidating the intricacies of 5-methylcytosine (5-mC) oxidation, which are at the core of the reversibility of this epigenetic modification; the three-dimensional structural characterization of eukaryotic DNA methyltransferases, which offered insights into the mechanisms that explain several disease-associated mutations; a more in-depth understanding of DNA methylation in development and disease; the possibility to learn about the biology of extinct species; the development of epigenetic clocks and their use to interrogate aging and disease; and the emergence of epigenetic biomarkers and therapies.

Endocranial development in non-avian dinosaurs reveals an ontogenetic brain trajectory distinct from extant archosaurs

Modern birds possess highly encephalized brains that evolved from non-avian dinosaurs. Evolutionary shifts in developmental timing, namely juvenilization of adult phenotypes, have been proposed as a driver of head evolution along the dinosaur-bird transition, including brain morphology. Testing this hypothesis requires a sufficient developmental sampling of brain morphology in non-avian dinosaurs. In this study, we harness brain endocasts of a postnatal growth series of the ornithischian dinosaur Psittacosaurus and several other immature and mature non-avian dinosaurs to investigate how evolutionary changes to brain development are implicated in the origin of the avian brain. Using three-dimensional characterization of neuroanatomical shape across archosaurian reptiles, we demonstrate that (i) the brain of non-avian dinosaurs underwent a distinct developmental trajectory compared to alligators and crown birds; (ii) ornithischian and non-avialan theropod dinosaurs shared a similar developmental trajectory, suggesting that their derived trajectory evolved in their common ancestor; and (iii) the evolutionary shift in developmental trajectories is partly consistent with paedomorphosis underlying overall brain shape evolution along the dinosaur-bird transition; however, the heterochronic signal is not uniform across time and neuroanatomical region suggesting a highly mosaic acquisition of the avian brain form.

Three-dimensional scanning measurement and characterization of air gap entrapped on air ventilation garments with different fabrics and clothing sizes

PurposeThe purpose of this paper is to determine the effect of clothing fabrics, sizes and air ventilation rate on the volume and thickness of the air gap under the air ventilation garments (AVGs).Design/methodology/approachThe geometric models of the human body and clothing were obtained by using a 3D body scanner. Then the distribution of the volume and thickness of the air gap for four clothing fabrics and three air ventilation rates (0L/S, 12L/S and 20L/S) were calculated by Geomagic software. Finally, a more suitable fabric was selected from the analysis to compare the distribution of the air gap entrapped for four clothing sizes (S, M, L and XL) and the three air ventilation rates.FindingsThe results show that the influence of air ventilation rate on the air gap volume and thickness is more obvious than that of the clothing fabrics and sizes. The higher is the air ventilation rate, the thicker is the air gap entrapped, and more evenly distributed is the air gap. It can be seen that the thickness of the air gap in the chest does not change significantly with the changes of the air ventilation rates, clothing fabrics and sizes, while the air gap in the waist is affected significantly.Originality/valueThis research provides a better understanding of the distribution of the air gap entrapped in ventilated garments, which can help in designing the optimal air gap dimensions and thus provide a basis and a reference for the design of the AVGs.

Assessment of internal quality of billets using ultrasonic three-dimensional layered characterization

Assessment of internal quality of billets using ultrasonic three-dimensional layered characterization

Investigation of the milled surface quality of SiCp/Al composite materials with a moderate SiCp volume fraction

Silicon carbide particle–reinforced aluminum matrix (SiCp/Al) composite materials are challenging to machine, leading to significant surface quality issues arising during milling. In this study, a single-factor experiment was conducted using carbide-coated tools to mill SiCp/Al composite materials with a 45% volume fraction of silicon carbide particles (SiCps). Scanning electron microscopy, roughness measuring instruments, and a three-dimensional optical profiler were employed to investigate the formation mechanisms of the machined surface morphologies, as well as the effects of milling parameters (milling speed, feed per revolution, and milling depth) on the surface micro-morphology of the SiCp/Al composite materials. This study assessed the suitability of various roughness characterization parameters for evaluating the milled surface of SiCp/Al composite materials, including the two-dimensional profile arithmetic mean deviation (Ra), profile root mean square deviation (Rq), and microscopic surface roughness 10-point height (Rz), as well as the three-dimensional arithmetic mean deviation of the surface profile (Sa), and root mean square deviation of the surface profile (Sq) roughness characterization parameters to evaluate the milled surface of the SiCp/Al composite materials. The findings suggest that the three-dimensional roughness characterization parameters more accurately reflected the changes in the surface roughness than the two-dimensional ones. When the milling speed increased from 0.05 to 1.2 mm/rev, Sa first decreased from 0.514 to 0.498 µm and then increased to 0.537 µm, while Sq first decreased from 0.637 to 0.616 µm and then increased to 0.658 µm. Ra, Rz, and Rq all increased with higher values of feed per revolution and milling depth.

Self-Lubrication Mechanism of Surface-Textured Polymer-Matrix Composites under the Induction of Frictional Stress.

Polymer-matrix composites have been widely used in the manufacture of seals, bearings, electrical insulators, and self-lubricating films as engineering applications move toward lighter weight, higher strength, and corrosion resistance. However, the high-speed shear effect of the friction pairs in relative motion leads to localized heating of the polymer surface, resulting in deformation or softening of the device. Herein, acer mono maple and canna leaves were used as templates to construct polymer-matrix sulfonated polyether-etherketone/polytetrafluoro-wax (SPEEK/PFW) composites with a surface-textured structure. As the bionic texture reduces the level of direct contact between the friction pairs, the frictional thermosoftening of SPEEK occurs in the localized areas of the bumps and leads to the release of PFW stored in textures, resulting in the formation of a soft polymer sliding layer in the worn area and greatly enhancing the frictional stability. By investigation of the tribological properties of textured SPEEK/PFW composites under different loads and sliding speeds, the mechanisms from surface wear to matrix softening and spontaneous construction of a slipping layer are summarized. The results of scanning electron microscopy and three-dimensional profilometer characterization of the wear scars show the surface state of SPEEK/PFW after friction, revealing the friction-thermotropic deformation of the surface texture. The results of this study not only improve our understanding of the frictional heat-induced surface self-lubrication mechanism of textured polymer composites but also provide a reference for the development of multiphase hybrid polymer-matrix composites with excellent self-lubrication properties.

Enhancing face-milling efficiency of wood–plastic composites through the application of genetic algorithm–back propagation neural network

ABSTRACT Wood–plastic composites (WPCs) have advanced physicochemical properties and are widely applied in various fields. How to achieve high-efficiency, high-quality machining of WPC is a pressing issue that WPC manufacturing enterprises need to address. To this end, this research focused primarily on improving the machinability of WPC with end milling experiments. In this work, a single-factor method was used to analyse the impact of axial milling depth, spindle speed, and tool rake angle on resultant forces and surface roughness. Main effects analysis was applied to explore the degree of influence of axial milling depth, spindle speed, and tool rake angle on cutting forces and surface roughness. Furthermore, three-dimensional characterisation techniques were utilised to analyse the surface morphology characteristics of WPC during end milling. Finally, a genetic algorithm–back propagation neural network was applied to develop prediction models for resultant force and surface roughness, and optimal milling conditions were identified as axial milling depth of 0.50 mm, spindle speed of 7841 r/min, and rake angle of 15°; these produced the lowest resultant force and surface roughness. The findings of this work are proposed as a guide for better cutting performance in the industrial production of WPC.

(Invited) Near-Field Optics and Its Applications in Nanoscale Materials: A Review

In this presentation, we first offer an overview of aperture-type scanning near field optical microscopy –a family of super-resolution imaging techniques based on evanescent waves, which can be combined with atomic force microscopy and are capable of subwavelength resolution nano-optical imaging. In the second part of this review, we will discuss a few applications in which our group capitalized on the super-resolution resolving power of SNOM to design specific nano-optical and nano-photonic systems for light harvesting, resistive memory device applications and nanoscale thermo-optical management, as well as to characterize nanoscale luminescent materials. Specific case studies that will be presented include the characterization of weakly photoluminescent and curved carbon dots for memory device applications, the three-dimensional characterization of plasmon-enhanced nanophotonic devices, as well as the development of near-field thermoreflectance imaging for nanophotonic-based thermal management applications. Collectively, our study well represents the versability of SNOM as a unique super-resolution nanophotonic tool for the investigation of light-matter interaction at the nanoscale.

Three-dimensional quantitative characterization of defects in inconel 625 superalloy based on deep learning image identification

Three-dimensional (3D) quantitative characterization of defects in superalloys is an important way to promote the ability of material design and service life prediction. In this work, 3D spatial distribution of defects for Inconel 625 superalloy manufactured by laser additive manufacturing (LAM) is carried out deep learning (DL) image identification technology and 3D image reconstruction. Firstly, computer tomography (CT) technology was used to obtain continuous slice images of sample. The U-net DL algorithm was applied to intelligently identify material defects in the continuous slices. On this basis, quantitative identification and analysis of spatial defect positions and typical sizes is achieved by using 3D reconstruction software. Compared with traditional threshold segmentation (TS) techniques, the defect recognition rate has significantly improved from 61.90 ​% to 95.00 ​%. This work provides a promising characterization method for efficient characterizing alloy defects and damage especially during material performance evaluation.

Methods for three-dimensional characterization of the acetabulum prior to pelvic reorientation osteotomy: a scoping review.

Periacetabular osteotomy is the gold standard treatment for acetabular dysplasia. The great variability of acetabular dysplasia requires a personalized preoperative planning improved by 3D reconstruction and computer-assisted surgery. To plan the displacement of the acetabular fragment by a pelvic osteotomy, it is necessary to define a reference plane and a method to characterize 3D acetabular orientation. A scoping review was performed on PubMed to search for articles with a method to characterize the acetabulum of native hips in a 3D reference frame. Ninety-eight articles out of 3815 reports were included. Three reproducible reference planes were identified: the anterior pelvic plane, the Standardization and Terminology Committee plane used in gait analysis, and the sacral base plane. The different methods for 3D analysis of the acetabulum were divided in four groups: global orientation, triplanar measurements, segmentation, and surface coverage of the femoral head. Two methods were found appropriate for reorientation osteotomies: the global orientation by a vector method and the triplanar method. The global orientation method relies on the creation of a vector from the acetabular rim, from the acetabular surface or from successive planes. Normalization of the global acetabular vector would correct acetabular dysplasia by a single alignment maneuver on an ideal vector. The triplanar method, based on angle measurements at the center of the femoral head, would involve correction of anomalies by considering axial, frontal, and sagittal planes. Although not directly fit for reorientation, the two others would help to candidate patients and verify both planning and postoperative result.

Spatiotemporal methods for estimating subsurface ocean thermal response to tropical cyclones

Abstract. Tropical cyclones (TCs), driven by heat exchange between the air and sea, pose a substantial risk to many communities around the world. Accurate characterization of the subsurface ocean thermal response to TC passage is crucial for accurate TC intensity forecasts and an understanding of the role that TCs play in the global climate system. However, that characterization is complicated by the high-noise ocean environment, correlations inherent in spatiotemporal data, relative scarcity of in situ observations, and the entanglement of the TC-induced signal with seasonal signals. We present a general methodological framework that addresses these difficulties, integrating existing techniques in seasonal mean field estimation, Gaussian process modeling, and nonparametric regression into an ANOVA decomposition model. Importantly, we improve upon past work by properly handling seasonality, providing rigorous uncertainty quantification, and treating time as a continuous variable, rather than producing estimates that are binned in time. This ANOVA model is estimated using in situ subsurface temperature profiles from the Argo fleet of autonomous floats through a multistep procedure, which (1) characterizes the upper-ocean seasonal shift during the TC season, (2) models the variability in the temperature observations, and (3) fits a thin-plate spline using the variability estimates to account for heteroskedasticity and correlation between the observations. This spline fit reveals the ocean thermal response to the TC passage. Through this framework, we obtain new scientific insights into the interaction between TCs and the ocean on a global scale, including a three-dimensional characterization of the near-surface and subsurface cooling along the TC storm track and the mixing-induced subsurface warming on the track's right side.

Welding load, temperature, and material flow in ultrasonic vibration enhanced friction stir lap welding of aluminum alloy to steel

To elucidate the effect of ultrasonic vibration on the welding process (welding load, thermal cycle, and material flow) of aluminum/steel dissimilar metals in friction stir lap welding, conventional friction stir lap welding (FSLW) and ultrasonic vibration enhanced friction stir lap welding (U-FSLW) were used to weld aluminum/steel dissimilar metals. The results indicate that applying ultrasonic vibration to the FSLW of aluminum/steel dissimilar metals can effectively decrease welding loads (tool torque, axial force, and spindle power), and it was found that the reduction in welding load was inversely proportional to the welding speed. The effect of additional ultrasonic vibration on axial force was the largest. Ultrasonic vibration had a significant preheating effect, and its thermal effect in the width and depth directions of the workpiece gradually weakened. Additional ultrasound can reduce the peak temperature during the welding process. The instantaneous state of the weld was obtained using the "emergency stop+emergency cooling" technology, and the three-dimensional visualization characterization of material flow near the keyhole was achieved using X-ray based computer tomography (CT). It was found that ultrasonic vibration could increase the material's plastic flow, change the steel structure's flow path, and significantly increase the steel particles' flow range near the pin tool. Compared with conventional FSLW, the changes in the macro/microstructure of U-FSLW joints were closely related to the welding thermal cycle and material flow.

In Situ Electrochemical Atomic Force Microscopy: From Interfaces to Interphases.

The electrochemical interface formed between an electrode and an electrolyte significantly affects the rate and mechanism of the electrode reaction through its structure and properties, which vary across the interface. The scope of the interface has been expanded, along with the development of energy electrochemistry, where a solid-electrolyte interphase may form on the electrode and the active materials change properties near the surface region. Developing a comprehensive understanding of electrochemical interfaces and interphases necessitates three-dimensional spatial resolution characterization. Atomic force microscopy (AFM) offers advantages of imaging and long-range force measurements. Here we assess the capabilities of AFM by comparing the force curves of different regimes and various imaging modes for in situ characterizing of electrochemical interfaces and interphases. Selected examples of progress on work related to the structures and processes of electrode surfaces, electrical double layers, and lithium battery systems are subsequently illustrated. Finally, this review provides perspectives on the future development of electrochemical AFM.

Three-Dimensional Characterization of Residual Stress in Aircraft Riveted Panel Structures

Three-Dimensional Characterization of Residual Stress in Aircraft Riveted Panel Structures