Three-dimensional Scanning Technique Research Articles

Running exercise decreases microglial activation in the medial prefrontal cortex in an animal model of depression

BackgroundRunning exercise effectively ameliorates depressive symptoms in humans and depression-like behaviors in animals, but the underlying mechanisms remain unclear. Microglia-mediated neuroinflammation plays a major role in the development of depression. The medial prefrontal cortex (mPFC) is a key brain region involved in depression and is sensitive to physical activity. Whether the antidepressant effect of running exercise involves changes in mPFC microglia is not understood. MethodsThe animals were subjected to chronic unpredictable stress (CUS) intervention followed by treadmill running. The sucrose preference test and elevated plus maze test or tail suspension test were used for behavioral assessment of the animals. The number of microglia in the mPFC was quantified by immunohistochemistry and stereology. The density and morphology of microglia were analyzed via immunofluorescence staining combined with three-dimensional laser scanning techniques. The mRNA expressions of inflammatory cytokines in the mPFC were examined via quantitative real-time PCR. ResultsRunning exercise effectively alleviated depressive-like behaviors in depression model animals. Running exercise reversed the increase in the number of microglia and the density of activated microglia in the mPFC of CUS animals. Running exercise effectively reversed the changes in microglia (reduced cell body area, total branch length and branch complexity) in the mPFC of CUS animals. Furthermore, running exercise regulated the gene expressions of pro−/antiinflammatory cytokines in the mPFC of CUS animals. ConclusionsOur results suggested that the antidepressant effects of running exercise may involve decreasing the number of activated microglia, reversing morphological changes in microglia in the mPFC, and reducing inflammatory responses.

Development of a personalized mask design method using three-dimensional scan data

Purpose This study aims to develop a novel design method to make personalized masks for the effective prevention of pandemic respiratory infectious disease.Design/methodology/approachThe changes in facial shape during speaking were analyzed using a three-dimensional (3D) scanning technique. In total, 13 anthropometric items were measured, and mask patterns were generated using a parametric pattern design method. Three sizing methods were proposed to reflect not only static but also dynamic body dimensions on the mask patterns.FindingsA significant increase or decrease was observed in 10 out of 13 measurement items. Based on this, four items were selected to be used in the mask pattern design. The nose and cheek areas of a mask were fixed to protect the respiratory tract against viruses. The lower jaw area was deformed to improve the fit.Social implicationsThis study is expected to provide fundamental data to understand the changes in facial shape during movement. In addition, it is expected that the development of individualized personal protective equipment with movement adaptability will facilitate an effective response to various pandemic respiratory diseases.Originality/valueIn order to develop a personal protective equipment (PPE) that has a good fit and can protect against pandemic respiratory infectious diseases, morphological analysis was attempted using 3D facial data. It would be possible to design various products and equipment to be worn on the face by using the method proposed in this study.

Development of an Orthosis to Compensate VolumetricDysmetria of Feet

The concept of symmetry applied to the two halves of the human body has been the subject of reflection by anatomists. One of the most common inequalities is dysmetry of the lower limbs (LL), especially the legs and/or feet. In the case of a height difference in the legs, if it is very pronounced, it is necessary to develop strategies capable of correcting or reducing its impact on the quality of life of people who live with it daily. A rare type of dysmetria is the volumetric difference of the feet, not accompanied by changes in the length of the legs. In these cases, filling with conventional orthopedic insoles to improve the fixation of the foot inside the shoe is completely inappropriate because it slightly increases the length of the respective lower limb, which is reflected in changes in the spine that can degenerate into severe scoliosis. To solve these problems, a volumetric compensation orthosis applicable to this type of situation was developed. Using modern three-dimensional scanning and 3D printing techniques, an orthosis was customized for placement inside the shoes of an individual with this volumetric anomaly. To ensure walking comfort, a common flexible material (TPU) was chosen, and the printing parameters were studied based on feedback given by the user. As a measure of the effectiveness of the developed product and to analyze the effect produced, tests were carried out to compare gait patterns before and after the correction was established. The results found showed an approximation to standard gait patterns, a considerable improvement in the fixation of the foot inside the shoe and an interchangeability that allows the use of the orthosis in any type of footwear, such as classic shoes, boots or sneakers.

Stability Analysis of Pillars in Underground Limestone Mine Using Three-Dimensional Scanning Techniques

Stability Analysis of Pillars in Underground Limestone Mine Using Three-Dimensional Scanning Techniques

Quantitative Assessment of Upper-Limb Volume: Implications for Lymphedema Rehabilitation?

Upper-limb lymphedema is a chronic condition characterized by the accumulation of lymphatic fluid in the arm or hand, resulting in swelling and functional impairment. The accurate and reliable volumetric assessment of limb volume is crucial for the correct management of lymphedema. This narrative review provides an overview of the different methods proposed in the literature for the volumetric assessment of upper-limb lymphedema. In more detail, several methods of volumetric assessment have been proposed in recent years, including water displacement, the centimetric method, perometry, bioimpedance spectroscopy, dual-energy X-ray absorptiometry, magnetic resonance imaging, computed tomography, and three-dimensional laser scanning techniques. On the other hand, each method is characterized by specific strengths and limitations in terms of accuracy, reliability, practicality, and cost-effectiveness. Moreover, factors including operator experience, equipment availability, and patient population characteristics might have several implications in the optimal assessment of upper-limb volume. In this context, a precise volumetric assessment is crucial to improving the rehabilitation framework, patient education, and research outcomes. As a result, the integration of emerging technologies is needed to improve the tailored management of patients with upper-limb lymphedema. In conclusion, volumetric assessment methods provide valuable insights in the management of upper-limb lymphedema, improving patient care, treatment outcomes, and research advancements. Future research should focus on testing these innovative solutions on larger samples of patients to enhance the reproducibility, accuracy, accessibility, and clinical utility of volumetric assessment methods in the complex treatment framework of upper-limb lymphedema.

Cataclastic Characteristics and Formation Mechanism of Dolomite Rock Mass in Yunnan, China

The dolomite rock mass on the slope of the Yanhe domestic waste incineration power plant was used as the research object. The macro- and micro-structural characteristics of intact rock blocks and rock discontinuities were analyzed qualitatively and quantitatively using in-hole television, wave velocity testing, three-dimensional laser scanning techniques, photogrammetry, image processing techniques, and scanning electron microscopy (SEM). The study shows that the degree of fracturing generally decreases with depth over the exposed borehole depth range, and the rock masses are generally very fractured. The wave velocity of dolomite generally increases with the depth of the borehole, and the integrity of the dolomite is either broken or extremely broken. The excavation profile reveals six sets of discontinuities and joints that are straight, smooth, interconnected, and largely unfilled. The angles of the structural bodies of different grain sizes are sharp, with roundness being angular and sharp-angled. The smaller the blocks, the more complex the surface morphology. SEM observations show that the ultramicroscopic fractures are not flat and smooth, and the fractures are folded. Fracturing mainly occurs along intercrystalline and crystal interfaces. These fracture features suggest that the fracturing of dolomite is mainly related to the original sedimentary construction and tectonism.

Characterization of Interlayer Bonding Mechanism Based on Interface Morphology in Double-Layered Asphalt Systems

The mechanism of interlayer bonding and its relationship with interface morphology in asphalt pavement is not well understood yet. This study aims at investigating the effect of interface morphology on the interlayer bonding performance of double-layered asphalt systems. Four double-layered asphalt systems were prepared with rubberized asphalt concrete (RAC), asphalt concrete (AC), and stone mastic asphalt (SMA) mixtures. To test the influence of different interlayer treatments, three conditions were studied: styrene-butadiene-styrene (SBS)-modified asphalt gravel seal (GS) coat (SBS-GS), rubber-modified asphalt gravel seal coat (RA-GS), and fiber-reinforced rubber–modified asphalt gravel seal coat (FR-GS). The influence of surface type and interface treatment on interface morphology and bonding properties were compared and analyzed using a series of indoor interlayer shear bonding tests under three temperature conditions in two phases. In addition, based on the three-dimensional (3D) scanning and reconstruction technique, the morphology of the nondestructively separated interface of double-layered systems with no interlayer treatment was obtained, and the mechanism of the influence of the interface morphology on the interlayer shear strength was analyzed in depth. The results showed that double-layered systems exhibited different macrotexture and roughness characteristics at interlayer surfaces, creating distinct interface morphology properties for each system type. Consequently, the interlayer bonding strength and performance of double-layered asphalt systems were affected accordingly. In this respect, the order of the interlayer shear strength of double-layered systems with different interlayer treatments at different temperatures ranked as RAC-13/RAC-20 > SMA-13/RAC-20 > SMA-13/AC-20 > AC-13/AC-20. It was demonstrated that the proposed interface area ratio (K) can be used for the characterization of the interface morphology and reflect the interlayer bonding state. Moreover, it was found that the interlayer treatment could influence the interface morphology to a certain extent and change the effective bonding between layers. As a result, the order of interlayer shear strength of different interlayer bonding treatments ranked as FR-GS> RA-GS > SBS-GS. Finally, aggregate gradation of the mixtures could also affect the morphological characteristics of the interface.

Degradation of Steel Rebar Tensile Properties Affected by Longitudinal Non-Uniform Corrosion.

Rebar corrosion is the primary cause of the durability degradation of reinforced concrete (RC) structures, where non-uniform corrosion is the typical pattern in engineering. This study experimentally and numerically investigated the tensile degradation properties of non-uniform corroded rebars. Corrosion morphology was accurately determined by three-dimensional (3D) laser scanning techniques, studying the characteristics of longitudinal non-uniform corrosion. The results showed that the non-uniformity of corrosion increased with an increase in corrosion levels. From tensile tests, the differences in nominal stress-strain curves among rebars with similar average corrosion levels indicated that corrosion non-uniformity has appreciable effects on the tensile behavior of rebars. The residual load-bearing capacity of corroded rebars was dominated by the reduced critical cross-section, while residual ductility was associated with the cross-section loss throughout the entire length of rebars. The degradation relations of nominal yield and ultimate strength, ultimate strain, and elongation after fracture were better correlated to the maximum cross-section loss than to the average volume loss. Additionally, numerical calculation based on the cross-sectional areas of corroded rebars was conducted to evaluate the tensile behavior of non-uniform corroded rebars. Equivalent distribution models simulating the longitudinal non-uniform corrosion were proposed, on the basis of probability characteristics of cross-sectional areas, for practical application of the numerical method.

Three-Dimensional Immersion Scanning Technique: A Scalable Low-Cost Solution for 3D Scanning Using Water-Based Fluid

Three-dimensional scanning technology has been traditionally used in the medical and engineering industries, but these scanners can be expensive or limited in their capabilities. This research aimed to develop low-cost 3D scanning using rotation and immersion in a water-based fluid. This technique uses a reconstruction approach similar to CT scanners but with significantly less instrumentation and cost than traditional CT scanners or other optical scanning techniques. The setup consisted of a container filled with a mixture of water and Xanthan gum. The object to be scanned was submerged at various rotation angles. A stepper motor slide with a needle was used to measure the fluid level increment as the object being scanned was submerged into the container. The results showed that the 3D scanning using immersion in a water-based fluid was feasible and could be adapted to a wide range of object sizes. The technique produced reconstructed images of objects with gaps or irregularly shaped openings in a low-cost fashion. A 3D printed model with a width of 30.7200 ± 0.2388 mm and height of 31.6800 ± 0.3445 mm was compared to its scan to evaluate the precision of the technique. Its width/height ratio (0.9697 ± 0.0084) overlaps the margin of error of the width/height ratio of the reconstructed image (0.9649 ± 0.0191), showing statistical similarities. The signal-to-noise ratio was calculated at around 6 dB. Suggestions for future work are made to improve the parameters of this promising, low-cost technique.

Three-dimensional simulation of the convective heat transfer coefficient of the human body under various air velocities and human body angles

This study aimed to investigate the effects of air velocity and human body angles on the convective heat transfer coefficient (hc) of the whole body and body segments. A 20-zone computational thermal manikin and climate chamber were constructed using a three-dimensional body scanning technique and ANSYS software. Subsequently, the hc values were calculated through computational fluid dynamics simulation and validated against the measurement and simulation results in the literature. Then, 50 cases (10 air velocities ranging from 0 to 20 m/s and 5 human body angles of 0°, 45°, 90°, 135°, and 180°) were considered to further analyze the combined effects of air velocity and human body angle on hc. The results indicated that the hc values of both the whole body and body segments increase exponentially with the air velocity. The whole body hc increases by approximately 23 times when the air velocity increases from 0.2 to 20 m/s. On the other hand, whole body hc is lower at a human body angle of 90° than at other angles; the human body angle has a significant effect on the hc of body segments. The difference in the hc of the whole body does not exceed 8.5 W/m2·K for the five human body angles, but the largest difference for the body parts reaches 52 W/m2·K. Finally, the combined effect of air velocity and human body angle on hc was expressed by a regression equation. This study can offer insights into the heat transfer process between the human body and its thermal environment, as well as human thermoregulation and skin burn injuries.

Method for visualizing the shear process of rock joints using 3D laser scanning and 3D printing techniques

This study presents a visualized approach for tracking joint surface morphology. Three-dimensional laser scanning (3DLS) and 3D printing (3DP) techniques are adopted to record progressive failure during rock joint shearing. The 3DP resin is used to create transparent specimens to reproduce the surface morphology of a natural joint precisely. The freezing method is employed to enhance the mechanical properties of the 3DP specimens to reproduce the properties of hard rock more accurately. A video camera containing a charge-coupled device (CCD) camera is utilized to record the evolution of damaged area of joint surface during the direct shear test. The optimal shooting distance and shooting angle are recommended to be 800 mm and 40°, respectively. The images captured by the CCD camera are corrected to quantitatively describe the damaged area on the joint surface. Verification indicates that this method can accurately describe the total sheared areas at different shear stages. These findings may contribute to elucidating the shear behavior of rock joints.

Three-dimensional Evaluation of Results After Dual-Plane Breast Augmentation with and Without Internal Suture Mastopexy.

In patients with breast atrophy and ptosis, it is necessary to correct both problems simultaneously. This study aimed to analyze breast morphological changes with a three-dimensional (3D) scanning technique to demonstrate the improvement effect of dual-plane breast augmentation combined with internal suture mastopexy. 3D breast surface scans were performed preoperatively and postoperatively in 24 patients (n = 35 breasts) undergoing internal suture mastopexy combined with prosthetic augmentation through the periareolar approach and 24 patients (48 breasts) undergoing simple dual-plane breast augmentation. Changes in linear distance, breast volume and volume distribution, breast projection, and nipple position were analyzed to assess the breast morphology. Compared with simple breast augmentation, augmentation combined with internal suture mastopexy was associated with a higher upper pole volume increase and greater medial and upward nipple displacement. After the surgery, the upper polevolume increased by an average of 10.6% in combined augmentation group and decreased by an average of 2.2% in the simple breast augmentation group. The measured breast projections were 24.8 ± 2.2% lower than expected in the combined group and 23.1 ± 4.1% lower than expected in the simple group, based on implant parameters recorded by the manufacturer. The nipple moved 0.2 ± 0.5cm laterally, 1.6 ± 0.6cm upward, and 2.8 ± 0.7cm anteriorly in the combined group and 0.9 ± 0.5cm laterally, 0.7 ± 0.6cm upward, and 3.0 ± 0.6cm anteriorly in the simple group. Dual-plane breast augmentation in addition to internal suture mastopexy appears to reposition breast tissue from the lower pole to fill in the deficient upper breast, pull the nipple medially and superiorly, and ultimately correct mild to moderate breast ptosis. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

In Vivo Analysis of Intraoral Scanner Precision Using Open-Source 3D Software

Intraoral three-dimensional scanning techniques could be used to improve dental practice, leading to an improved overall quality of the prosthetic devices and improved comfort for the patient. An accurate and precise intraoral scanner allows proper diagnosis, follow-up evaluation, and prosthesis application. The aim of this research is to evaluate the precision of an intraoral scanners (Medit i500, Medit Corp., Seoul, Korea), using open-source software in the digital workflow. The precision was compared through repetitions of the scanning process of the upper dental arch, following superimpositions in the whole 3D arch area. It was possible to display colorimetric maps for qualitative comparison, and the deviations of the values were classified as clinically acceptable. Within the limitation of this study, the clinically acceptable in vivo frequency of points’ deviation, or the precision, was obtained in 98.8% ± 1.4%; therefore, the use of open-source software can be a viable option in the digital workflow, improving patient follow ups with the 3D model superimposition.

Effect of Leaching Behavior on the Geometric and Hydraulic Characteristics of Concrete Fracture.

The leaching of material from concrete fracture surfaces has an impact on the structural concrete in service, but the number of studies that consider the effect of the coupling of the leaching, fracture geometry and hydraulic processes on concrete fractures is insufficient. In this study, a series of experiments was conducted, and a leaching model proposed, to investigate the mechanism of leaching behavior on the geometric and hydraulic characteristics of concrete fractures. Following the leaching experiment, the evolution of fracture geometric characteristics was observed by a three-dimensional (3D) laser scanning technique, finding that the fracture produces residual leached depth and local uneven leaching, which results in a decrease in roughness. The hydraulic characteristics were then investigated by permeability tests, and it was found that the fracture hydraulic aperture and permeability increase monotonically with leaching time. A simulation of fluid flow in a numerical fracture revealed the effect of residual leached depth and a decrease in roughness on the hydraulic characteristics. Finally, based on the analysis of the chemical composition of the leaching solution, a leaching model of concrete rough fracture surface is proposed and the mechanism of leaching behavior is discussed. These new findings are useful for the understanding of the development of leaching, local to concrete fracture surfaces.

Digital body preservation: Technique and applications.

High-fidelity anatomical models can be produced with three-dimensional (3D) scanning techniques and as such be digitally preserved, archived, and subsequently rendered through various media. Here, a novel methodology-digital body preservation-is presented for combining and matching scan geometry with radiographic imaging. The technique encompasses joining layers of 3D surface scans in an anatomical correct spatial relationship. To do so, a computed tomography (CT) volume is used as template to join and merge different surface scan geometries by means of nonrigid registration into a single environment. In addition, the use and applicability of the generated 3D models in digital learning modalities is presented. Finally, as computational expense is usually the main bottleneck in extended 3D applications, the influence of mesh simplification in combination with texture mapping on the quality of 3D models was investigated. The physical fidelity of the simplified meshes was evaluated in relation to their resolution and with respect to key anatomical features. Large- and medium-scale features were well preserved despite extensive 3D mesh simplification. Subtle fine-scale features, particular in curved areas demonstrated the major limitation to extensive mesh size reduction. Depending on the local topography, workable mesh sizes ranging from 10% to 3% of the original size could be obtained, making them usable in various learning applications and environments.

Digital Body Preservation

Detailed anatomical models can be produced with three‐dimensional (3D) scanning techniques and as such be digitally preserved, archived and subsequently rendered through various media. Here, a novel methodology is presented for combining and matching scan geometry with radiographic imaging. The technique encompasses joining layers of 3D surface scans in an anatomical correct spatial relationship. To do so, a computed tomography (CT) volume is used as template to join and merge different surface scan geometries by means of non‐rigid registration into a single environment. This results in a digital model that can be used in multiple digital learning environments. Finally, as computational expense is usually the main bottleneck in extended 3D applications, the influence of mesh simplification in combination with texture mapping on the quality of 3D models was investigated. The fidelity of the simplified meshes was evaluated in relation to their resolution and with respect to key anatomical features. Large‐ and medium‐scale features were well preserved despite extensive 3D mesh simplification. Subtle fine‐scale features, particular in curved areas demonstrated the major limitation to extensive mesh size reduction. Depending on the local topography, workable mesh sizes ranging from 10% to 3% of the original size could be obtained, making them usable in various learning applications and environments.

On the methods of recognition and classification of laser reflection points based on the Terrasolid software module on the Bentley Microstation platform

Nowadays, the use of the three-dimensional laser scanning technique in performing various scientific research comes to the fore, since this technology is one of the most developed and effective methods for analyzing the state of transport infrastructure objects and geodetic monitoring. The purpose of this paper is to develop an author’s algorithm for the classification of laser reflection points, based on the specialized Terrasolid software on the Bentley Microstation platform. The object of the research is the campus of the territory of the Federal State Budgetary Educational Institution of Higher Education “Kuban State Technological University”. The subject of the research is the possibility of optimizing the process of classification of laser reflection points on the campus of the university territory. The result of the study is the author’s algorithm for the classification of laser reflection points.

Experimental investigation on the performance degradation of helicopter rotor due to ice accretion

Helicopter rotor performance can be significantly altered by ice accretion which directly degrades the handling qualities and safety during flight. To obtain understanding into the effect of ice accretion on a helicopter rotor in forward flight under different icing environments, an experimental campaign was conducted in an icing wind tunnel using a rotor model with diameter at 2 m. Research was emphasized on revealing effect of liquid water content and static temperature on the rotor performance degradation. The dynamic thrust and torque of the rotor were measured by a six-component balance. Ice shape of the airfoils at specific rotor blade spanwise locations was obtained through the ice cutting process; meanwhile, the entire ice topology on the blade was scanned by means of the three-dimensional scanning technique. Results showed that ice was mainly accreted on the leading edge and lower surface of the blade. The static temperature of a icing cloud has a noticeable effect on the regime of accreted ice. The ice formation was transparent glaze at −8°C and transformed to milky rime when changed the static temperature to −20°C. Comparing to rime ice, the glaze ice on the blade is more influential to the rotor performance degradation. Particular attention is given to the fact that under extreme icing conditions, over 30% degradation of transient rotor thrust was observed.

Application of Replicas in the Measurement of the Wear of Forging Dies with Deep Hollows Using a Laser Scanner

Abstract This article discusses the possibilities of using replicas of the geometry of the tool shaping the product in the process of hot precision forging for the control of geometrical characteristics, with the use of the three-dimensional (3D) laser scanning technique. Two types of masses were selected for the studies and used to create replicas with similar parameters, with which a forging die with a deep working impression, applied in the process of forward extrusion, was filled. The obtained results demonstrated that, based on selected parameters characterizing the replicate masses and tests, it is possible to select the optimal mass for 3D scanning, due to the best mapping of the surface layer. With the proposed approach, it is possible to perform tests that do not damage forging dies with deep working impressions and to support the process by making decisions concerning the tools’ further operation through a reliable determination of their wear.

An Intraoperative Measurement Method of Breast Symmetry Using Three-Dimensional Scanning Technique in Reduction Mammaplasty.

Intraoperative symmetrical assessment plays a decisive role in the aesthetic results of reduction mammaplasty, but it depends mostly on the surgeons'experience that may be biased by individual subjective factors. This study was intended to propose an objective method based on a hand-held three-dimensional (3D) scanner to assist intraoperative symmetrical assessment, aiming to achieve better aesthetic results in reduction mammaplasty. Sixty patients were enrolled in the study from April 2018 to January 2020. Intraoperative 3D scanning was routinely performed on 29 patients (study group) to assist symmetrical adjustments during breast shaping. 3D surface scanning data of both groups were obtained at 3 months postoperatively to objectively assess breast symmetry. Postoperative symmetry scores in five aspects, including nipple-areolar complex position, inframammary-fold height, breast size, shape, and footprint, were rated by six independent observers based on anonymized photographs to subjectively evaluate pre- and postoperative breast symmetry of the two groups. The bilateral breast volume difference of the study group was significantly smaller than the control group (39.1 vs. 113.3cm3, p = 0.001), as well as the difference in nipple to inframammary-fold distance (2.79 vs. 7.43mm, p = 0.01). The observer-reported results showed that breast reduction significantly improved postoperative symmetry in all five aspects compared with preoperative symmetry in the study group (P<0.001). Furthermore, postoperative symmetrical ratings of all five aspects in the study group were statistically better than the control group (P<0.05). Intraoperative 3D scanning provided a reliable method to assist symmetry adjustments and ensure better postoperative breast symmetry in reduction mammaplasty. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .