3D Model Research Articles

Weak bond evaluation of lap bonding structures by SH guided waves using EMATs

ABSTRACT In this research, simulations and experiments were conducted for the bonding quality evaluation of an aluminum bonding structure, based on the SH guided wave analysis. In order to simulate the propagation of SH waves in the bonded structure, a 3D finite element model was established based on interfacial spring stiffness modeling. The frequency-wavenumber diagram was obtained by doing Fourier transform along the spatial axis in the time frequency domain simulation results. At the same time, the influence of the bonding interface weakening on the propagation characteristics of the guided wave was analyzed. The simulated dispersion curves of SH-guided waves in different bonding states were in good agreement with the theoretically results. In addition, a periodic permanent magnet electromagnetic acoustic transducer (PPM-EMAT) 3D finite element model was established. An optimized transducer was fabricated to excite pure SH0 mode. Then, a series of aluminum lap bonding structures with different bonding states were prepared. The effect of bonding interfaces on the propagation characteristics of SH waves was investigated. The interfacial spring stiffness can be determined when the STFT of the SH waves matches the theoretical dispersion curves. Thus, this method demonstrated an ultrasonic way to distinguish the weakening of the bonding structures.

An evaluation of consumer smartphones for generating bolus and surface mould applicators for radiation oncology.

The use of Computed Tomography (CT) imaging data to create 3D printable patient-specific devices for radiation oncology purposes is already well established in the literature and has shown to have superior conformity than conventional methods. Using non-ionizing radiation imaging techniques such as photogrammetry or laser scanners in-lieu of a CT scanner presents many desirable benefits including reduced imaging dose and fabrication of the device can be completed prior to simulation. With recent advancements in smartphone-based technology, photographic and LiDAR-based technologies are more readily available than ever before and to a high level of quality. As a result, these non-ionizing radiation imaging methods are now able to generate patient-specific devices that can be acceptable for clinical use. In this work, we aim to determine if smartphones can be used by radiation oncologists or other radiation oncology staff to generate bolus or brachytherapy surface moulds instead of conventional CT with equivalent or comparable accuracy. This work involved two separate studies: a phantom and participant study. For the phantom study, a RANDO anthropomorphic phantom (limited to the nose region) was used to generate 3D models based on three different imaging techniques: conventional CT, photogrammetry & LiDAR which were both acquired on a smartphone. Virtual boliwere designed in Blender and 3D printed from PLA plastic material. Theconformity of each printed boli was assessed by measuring the air gap volume and approximate thickness between the phantom & bolus acquired together on a CT. For the participant study, photographs, and a LiDAR scan of four volunteers were captured using an iPhone 13 Pro™ to assess their feasibility for generating human models. Each virtual 3D model was visually assessed to identify any issues in their reconstruction. The LiDAR models wereregistered to the photogrammetry models where a distance to agreement analysis was performed to assess their level of similarity.Additionally, a 3D virtual bolus was designed and printed using ABS material from all models to assess their conformity onto the participants skin surface using a verbal feedback method. The photogrammetry derived bolus showed comparable conformity to the CT derived bolus while the LiDAR derived bolus showed poorer conformity as shown by their respective air gap volume and thickness measurements. The reconstruction quality of both the photogrammetry and LiDAR models of the volunteers was inadequate in regions of facial hair and occlusion, which may lead to clinically unacceptable patient-specific device that are created from these areas. All participants found the photogrammetry 3D printed bolus to conform to their nose region with minimal room to move while three of the four participants found the LiDAR was acceptable and could be positioned comfortably over their entire nose. Smartphone-based photogrammetry and LiDAR software show great potential for future use in generating 3D reference models for radiation oncology purposes. Further investigations into whether they can be used to fabricate clinically acceptable patient-specific devices on a larger and more diverse cohort of participants and anatomical locations is required for a thorough validation of their clinical usefulness.

Research progress in the development of 3D skin models and their application to in vitro skin irritation testing.

Toxicological assessment of chemicals is crucial for safeguarding human health and the environment. However, traditional animal experiments are associated with ethical, technical, and predictive limitations in assessing the toxicity of chemicals to the skin. With the recent development of bioengineering and tissue engineering, three-dimensional (3D) skin models have been commonly used as an alternative for toxicological studies. The skin consists of the subcutaneous, dermis, and epidermis. All these layers have crucial functions such as physical and biological protection and thermoregulation. The epidermis is the shallowest layer protecting against external substances and media. Because the skin is the first contact point for many substances, this organ is very significant for assessing local toxicity following skin exposure. According to the classification of the United Nations Global Harmonized System, skin irritation is a major potentially hazardous characteristic of chemicals, and this characteristic must be accurately assessed and classified for enhancing chemical safety management and preventing and reducing chemical accidents. This review discusses the research progress of 3D skin models and introduces their application in assessing chemical skin irritation.

Chemical treatment in 3D dental model production for clear aligners via additive manufacturing: a comprehensive evaluation

Purpose Stereolithography (SLA) additive manufacturing (AM) technique has enabled the production of inconspicuous and aesthetically pleasing orthodontics that are also hygienic. However, the staircase effect poses a challenge to the application of invisible orthodontics in the dental industry. The purpose of this study is to implement chemical postprocessing technique by using isopropyl alcohol as a solvent to overcome this challenge. Design/methodology/approach Fifteen experiments were conducted using a D-optimal design to investigate the effect of different concentrations and postprocessing times on the surface roughness, material removal rate (MRR), hardness and cost of SLA dental parts required for creating a clear customized aligner, and a container was constructed for chemical treatment of these parts made from photocurable resin. Findings The study revealed that the chemical postprocessing technique can significantly improve the surface roughness of dental SLA parts, but improper selection of concentration and time can lead to poor surface roughness. The optimal surface roughness was achieved with a concentration of 90 and a time of 37.5. Moreover, the dental part with the lowest concentration and time (60% and 15 min, respectively) had the lowest MRR and the highest hardness. The part with the highest concentration and time required the greatest budget allocation. Finally, the results of the multiobjective optimization analysis aligned with the experimental data. Originality/value This paper sheds light on a previously underestimated aspect, which is the pivotal role of chemical postprocessing in mitigating the adverse impact of stair case effect. This nuanced perspective contributes to the broader discourse on AM methodologies, establishing a novel pathway for advancing the capabilities of SLA in dental application.

The structural landscape and diversity of Pyricularia oryzae MAX effectors revisited.

Magnaporthe AVRs and ToxB-like (MAX) effectors constitute a family of secreted virulence proteins in the fungus Pyricularia oryzae (syn. Magnaporthe oryzae), which causes blast disease on numerous cereals and grasses. In spite of high sequence divergence, MAX effectors share a common fold characterized by a ß-sandwich core stabilized by a conserved disulfide bond. In this study, we investigated the structural landscape and diversity within the MAX effector repertoire of P. oryzae. Combining experimental protein structure determination and in silico structure modeling we validated the presence of the conserved MAX effector core domain in 77 out of 94 groups of orthologs (OG) identified in a previous population genomic study. Four novel MAX effector structures determined by NMR were in remarkably good agreement with AlphaFold2 (AF2) predictions. Based on the comparison of the AF2-generated 3D models we propose a classification of the MAX effectors superfamily in 20 structural groups that vary in the canonical MAX fold, disulfide bond patterns, and additional secondary structures in N- and C-terminal extensions. About one-third of the MAX family members remain singletons, without strong structural relationship to other MAX effectors. Analysis of the surface properties of the AF2 MAX models also highlights the high variability within the MAX family at the structural level, potentially reflecting the wide diversity of their virulence functions and host targets.

Aggregation of human osteoblasts unlocks self-reliant differentiation and constitutes a microenvironment for 3D-co-cultivation with other bone marrow cells

Skeletal bone function relies on both cells and cellular niches, which, when combined, provide guiding cues for the control of differentiation and remodeling processes. Here, we propose an in vitro 3D model based on human fetal osteoblasts, which eases the study of osteocyte commitment in vitro and thus provides a means to examine the influences of biomaterials, substances or cells on the regulation of these processes. Aggregates were formed from human fetal osteoblasts (hFOB1.19) and cultivated under proliferative, adipo- and osteoinductive conditions. When cultivated under osteoinductive conditions, the vitality of the aggregates was compromised, the expression levels of the mineralization-related gene DMP1 and the amount of calcification and matrix deposition were lower, and the growth of the spheroids stalled. However, within spheres under growth conditions without specific supplements, self-organization processes occur, which promote extracellular calcium deposition, and osteocyte-like cells develop. Long-term cultivated hFOB aggregates were free of necrotic areas. Moreover, hFOB aggregates cultivated under standard proliferative conditions supported the co-cultivation of human monocytes, microvascular endothelial cells and stromal cells. Overall, the model presented here comprises a self-organizing and easily accessible 3D osteoblast model for studying bone marrow formation and in vitro remodeling and thus provides a means to test druggable molecular pathways with the potential to promote life-long bone formation and remodeling.

Illusions of Self-Motion during Magnetic Resonance-Guided Focused Ultrasound Thalamotomy for Tremor.

Brain networks mediating vestibular perception of self-motion overlap with those mediating balance. A systematic mapping of vestibular perceptual pathways in the thalamus may reveal new brain modulation targets for improving balance in neurological conditions. Here, we systematically report how magnetic resonance-guided focused ultrasound surgery of the nucleus ventralis intermedius of the thalamus commonly evokes transient patient-reported illusions of self-motion. In 46 consecutive patients, we linked the descriptions of self-motion to sonication power and 3-dimensional (3D) coordinates of sonication targets. Target coordinates were normalized using a standard atlas, and a 3D model of the nucleus ventralis intermedius and adjacent structures was created to link sonication target to the illusion. A total of 63% of patients reported illusions of self-motion, which were more likely with increased sonication power and with targets located more inferiorly along the rostrocaudal axis. Higher power and more inferiorly targeted sonications increased the likelihood of experiencing illusions of self-motion by 4 and 2 times, respectively (odds ratios = 4.03 for power, 2.098 for location). The phenomenon of magnetic vestibular stimulation is the most plausible explanation for these illusions of self-motion. Temporary unilateral modulation of vestibular pathways (via magnetic resonance-guided focused ultrasound) unveils the central adaptation to the magnetic field-induced peripheral vestibular bias, leading to an explicable illusion of motion. Consequently, systematic mapping of vestibular perceptual pathways via magnetic resonance-guided focused ultrasound may reveal new intracerebral targets for improving balance in neurological conditions. ANN NEUROL 2024.

3D Modelling Approach to Enhance the Characterization of a Bronze Age Nuragic Site

3D Modelling Approach to Enhance the Characterization of a Bronze Age Nuragic Site

Analysis of Anatomy and Age-related Changes in Infraorbital Cheek Using Computed Tomography.

There is no consensus regarding age-related facial anatomical changes. In this study, aging-related changes in soft and hard cheek tissues were quantitatively analyzed using computed tomography. We performed a retrospective study of 90 Asian females who underwent facial computed tomography. Three-dimensional model of soft tissue in apple zone was reconstructed, and age-related changes in fat volume and pyriform aperture area were quantified using Mimics software. The apple zone is an aesthetic unit of the infraorbital cheek, with soft tissue located between the lateral wall of the pyriform aperture and the zygomatic major muscle. The superficial fat volume significantly decreased with age (P < 0.05). In contrast, a significant decrease in total fat volume was only observed between the young and old groups (P < 0.05). In linear regression modeling, age was a significant predictor of pyriform aperture area (R2 = 0.194, P < 0.001). These results suggest that superficial fat atrophy and bone remodeling in the cheek with age, and both of which combine to contribute to an aging facial appearance. 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 .

Feasibility and impact of three-dimensional (3D) printing technology in simulated teaching of congenital malformations

AimsThis study aimed to investigate the feasibility and effectiveness of utilizing three-dimensional (3D) printing technology in the simulation teaching of congenital malformations.MethodsWe conducted a comparative analysis between an experimental group that received traditional teaching supplemented with 3D printing model demonstrations and hands-on model operation, and a control group that received traditional teaching methods. Various parameters, including classroom interest, classroom interaction, learning enthusiasm, disease awareness, teaching satisfaction, and independent operation confidence, were assessed, along with theoretical and practical tests.ResultsThe results showed no significant difference in theoretical test scores between the two groups (91.92 ± 15.04 vs. 89.44 ± 14.89), but the practical test revealed a significantly higher number of qualified trainees in the experimental group compared to the control group (23 vs. 8). In terms of classroom engagement, both groups exhibited similar levels of interest (8.08 ± 1.52 vs. 8.74 ± 0.984), classroom interaction (7.88 ± 1.97 vs. 8.7 ± 1.33), learning enthusiasm (8.81 ± 1.021 vs. 8.52 ± 1.189), and disease awareness (8.58 ± 0.99 vs. 8.58 ± 0.99). However, the experimental group demonstrated significantly higher teaching satisfaction (8.81 ± 1.06 vs. 9.19 ± 0.96) and greater operation confidence (7.67 ± 2.56 vs. 5.5 ± 2.79) than the control group.Conclusion3D printing technology can be effectively utilized to create surgical teaching models, enhancing the confidence of standardized training doctors and improving teaching outcomes.

Study on Flow Characteristics of Integrated Natural Circulation Reactor Under Inclined Conditions

In order to study the flow characteristics of an integrated natural circulation reactor under inclined conditions, a typical three-dimensional analysis model of natural circulation was established. The natural circulation under inclined conditions was numerically simulated using the computational fluid dynamics method, and the velocity and temperature distribution characteristics of heat exchangers and mixed-flow channels with different inclined angles were analyzed. The results show that as the inclination angle of the heat exchanger flow rate increases, there is a spatial migration phenomenon corresponding to the direction of the average flow rate. A large inclination angle will lead to a serious deterioration of the natural circulation capacity in the lower channel. Under inclined conditions, there is a phenomenon of temperature stratification in the mixed-flow channel.

Development of Learning Media Integrated Module Application Based on Socio-Scientific Issues Enriched Augmented Reality on Electrolysis Cell Material

This study aims to develop learning media integrated module applications based on socio-scientific issues enriched by augmented reality on electrolysis cell material and test the feasibility and validity of chemistry learning media products developed. The research method used is research and development (R&amp;D) using the 3D model adopted from the 4D model developed by Thiagrajan et al. (1974: 5), which consists of 3 stages, namely: define, design, and development. This research is only limited to the development stage. The instruments used in this research are validation and readability test questionnaires. The validators consisted of 2 people, namely one lecturer from the Chemistry Department of the State University of Malang and one chemistry teacher from SMAN 2 Batu, as media and material experts. The readability test was conducted on 29 undergraduate students of the Chemistry Education class 2022 at the State University of Malang, assuming they had taken the subject during class XII in senior high school. The results showed that the validity of the material and media included very feasible criteria with 98.24% and 96.81%, respectively, in addition to the average of all aspects of the readability test assessed having a percentage of 91.77%.

Quantitative Analysis and 3D Visualization of Crack Behavior in 3D-Printed Rock-Like Specimens with Single Flaw Using In-Situ Micro-CT Imaging

Abstract3D printing technology allows for precise control of preparing complex geometries and internal defects in printed rock analogs, while in-situ Micro-CT imaging enables real-time observation of crack behavior. The combination of these technologies offers a new research approach for studying rock crack behavior. In this study, 3D-printed rock-like specimens containing a pre-existing flaw were prepared using a gypsum powder-based 3D printer. An advanced in-situ Micro-CT system equipped with a loading device was used to quantitatively and visually investigate the crack behavior in 3D-printed specimens under uniaxial compression testing. 2D CT images obtained from in-situ compression testing at different deformations could be used to reconstruct a 3D model and visually identify the crack patterns of the extracted cracks in 3D-printed specimens. The initiation angle of cracks, volume of the pre-existing flaw, volume of newly formed cracks, and damage value with respect to strains were analyzed to quantitatively investigate crack behavior. The results indicated that within the 3D-printed specimens, tensile cracks were first initiated near the internal flaw, followed by the occurrence of shear cracks or tensile-shear mixed cracks at the flaw tips. Additionally, there was a negative linear correlation between the initiation angle of newly formed cracks and the initial flaw angle. For flaw angles in the range of 0° ≤ α ≤ 45°, a higher number of newly formed cracks were observed in the 3D-printed specimens, and the rates of increase in crack volume and damage values with strain were faster. However, for flaw angles in the range of 45° &lt; α ≤ 90°, the results showed the opposite trend. Furthermore, through comparison with the crack behavior of natural rocks containing a single flaw, it was found that the failure modes and crack behavior of the 3D-printed specimens exhibit certain similarities with natural rocks.

Structural Analysis of an Off-Road Vehicle Suspension System Using CATIA and ANSYS

This project delves into the structural analysis of an off-road vehicle suspension system, employing cutting-edge software tools such as CATIA and ANSYS. Off-road vehicles necessitate robust suspension systems capable of withstanding harsh terrain conditions while ensuring vehicle stability, manoeuvrability, and passenger comfort. The study focuses on evaluating the structural integrity, performance, and behaviour of the suspension system under diverse load conditions and terrain scenarios. This project focuses on conducting a comprehensive structural analysis of an off-road vehicle suspension system using advanced engineering software tools, specifically CATIA and ANSYS. CATIA is a powerful computer-aided design (CAD) software known for its capabilities in creating detailed 3D models, while ANSYS is a leading finite element analysis (FEA) software used for simulating structural behaviour and analyzing mechanical systems. Keywords: suspension system, CATIA v5, ANSYS, iterations, FEA.

Evaluation of Anti‐inflammatory Activity of Garlic Extracts in 3D Bioprinted Skin Equivalents

Ongoing obstacles in preclinical drug testing have raised significant concerns within the pharmaceutical industry. Recently, utilizing the potential of three‐dimensional (3D) bioprinting offers a solution for creating tissue models for screening of the effectiveness and safety of new drugs. In this study, the anti‐inflammatory potential of garlic extracts is assessed, specifically N‐Benzyl‐N‐methyl‐dodecan‐1‐amine (BMDA), using a 3D bioprinted artificial skin model. Comprehensive physicochemical characterization and immunocytochemical analysis demonstrate that the 3D bioprinted skin model exhibits structures and functions resembling human skin. BMDA treatment in a prepared skin model reveals its capacity to mitigate H2O2‐induced oxidative stress and trigger anti‐inflammatory responses. Notably, BMDA reduces the expression of pro‐inflammatory cytokines and chemokines by downregulating NF‐κB and mitogen‐activated protein kinase inflammatory signaling pathways. In summary, our findings highlight the potential of an artificial skin model as a robust platform for the development of new drugs.

How far are we off? Analyzing the accuracy of surgical margin relocation in the head and neck.

Positive surgical margin rates remain high in head and neck cancer surgery. Relocation is challenging given the complex, three-dimensional (3D) anatomy. Prospective, multi-institutional study to determine accuracy of head and neck surgeons and pathologists relocating margins on virtual 3D specimen models using written descriptions from pathology reports. Using 3D models of 10 head and neck surgical specimens, each participant relocated 20 mucosal margins (10 perpendicular, 10 shave). A total of 32 participants, 23 surgeons and 9 pathologists, marked 640 margins. Of the 320 marked perpendicular margins, 49.7% were greater than 1 centimeter from the true margin with a mean relocation error of 10.2 mm. Marked shave margins overlapped with the true margin a mean 54% of the time, with no overlap in 44 of 320 (13.8%) shave margins. Surgical margin relocation is imprecise and challenging even for experienced surgeons and pathologists. New communication technologies are needed.

MODELLING AND 3D PRINTING OF JCB ARM

The Hydraulic excavator machines are heavy duty earth movers consisting of a boom, arm and bucket. It works on principle of hydraulic fluid with hydraulic cylinder and hydraulic motors. The Hydraulic excavator arm operation require coordinated movement of boom, arm and bucket. The important criteria for the design to be safe is that, the digging forces developed by actuators must be greater than that of the resistive forces offered by the surface to be excavated. The main objective of this paper is to perform design and analysis Excavator Arm for the calculated Force. The CATIA software is used for making the 3D model of the excavator arm linkage. By using ANSYS workbench software analysis of the excavator arm is done at existing digging force and lifting force. Excavator bucket is very crucial element of hydraulic excavator. The whole loads of excavated materials have been carried out by this element. As the present mechanism used in excavator arm is subjected to deformation and bending stresses during lifting and digging operation respectively, because of which failure occurs frequently at the bucket end of the arm. Keywords: Excavator arm, Digging force, CATIA, ANSYS 16.0.

Challenges and directions for digital twin implementation in otorhinolaryngology.

Digital twin technology heralds a transformative era in Otorhinolaryngology (ORL), merging the physical and digital worlds to offer dynamic, virtual models of physical entities or processes. These models, capable of simulating, predicting, and optimizing real-world counterparts, are evolving from static replicas to intelligent, adaptive systems. Fueled by advancements in communication, sensor technology, big data analytics, Internet of Things (IoT), and simulation technologies, artificial intelligence (AI), digital twins in ORL promise personalized treatment planning, virtual experimentation, and therapeutic intervention optimization. Despite their potential, the integration of digital twins in ORL faces challenges including data privacy and security, data integration and interoperability, computational demands, model validation and accuracy, ethical and regulatory considerations, patient engagement, and cost and accessibility issues. Overcoming these challenges requires robust data protection measures, seamless data integration, substantial computational resources, rigorous validation studies, ethical transparency, patient education, and making the technology accessible and affordable. Looking ahead, the future of digital twins in ORL is bright, with advancements in AI and machine learning, omics data integration, real-time monitoring, virtual clinical trials, patient empowerment, seamless healthcare integration, longitudinal data analysis, and collaborative research. These developments promise to refine diagnostic and treatment strategies, enhance patient care, and facilitate more efficient and tailored ORL research, ultimately leading to more effective and personalized ORL management.

Comparison between 2D and 3D microstructures and implications for metamorphic constraints using a chloritoid–garnet-bearing mica schist

Abstract. Despite the fact that rock textures depend on the 3D spatial distribution of minerals, our tectono-metamorphic reconstructions are mostly based on a 2D visualisation (i.e. thin sections). This work compares 2D and 3D investigations of petrography and microstructures, modal abundances, and local bulk rock composition and their implication for P–T estimates, showing the pros and cons and reliability of 2D analysis. For this purpose, a chloritoid–garnet-bearing mica schist from the Dora-Maira Massif in the Western Alps has been chosen. In particular, for 2D a thin section scan has been combined with chemical X-ray maps, whereas for 3D the X-ray computerised axial microtomography (µCT) has been applied. Two-dimensional investigations are readily accessible and straightforward but do not consider the entire rock volume features. Conversely, the rise of 3D techniques offers a more comprehensive and realistic representation of metamorphic features in the 3D space. However, they are computationally intensive, requiring specialised tools and expertise. The choice between these approaches should be based on the research aims, available resources, and the level of detail needed to address specific scientific questions. Nevertheless, despite differences in the modal distribution, the estimated bulk rock compositions and relative thermodynamic modelled phase fields show similarities when comparing the 2D and 3D results. Also, since different thin section cut orientations may influence the results and consequent interpretations, three different cuts from the 3D model have been extrapolated and discussed (i.e. XZ, YZ, and XY planes of the finite-strain ellipsoid). This study quantitatively corroborates the reliability of the thin section approach for tectono-metamorphic reconstructions, still emphasising that 3D visualisation can help understand rock textures.

Saliency-Guided Point Cloud Compression for 3D Live Reconstruction

3D modeling and reconstruction are critical to creating immersive XR experiences, providing realistic virtual environments, objects, and interactions that increase user engagement and enable new forms of content manipulation. Today, 3D data can be easily captured using off-the-shelf, specialized headsets; very often, these tools provide real-time, albeit low-resolution, integration of continuously captured depth maps. This approach is generally suitable for basic AR and MR applications, where users can easily direct their attention to points of interest and benefit from a fully user-centric perspective. However, it proves to be less effective in more complex scenarios such as multi-user telepresence or telerobotics, where real-time transmission of local surroundings to remote users is essential. Two primary questions emerge: (i) what strategies are available for achieving real-time 3D reconstruction in such systems? and (ii) how can the effectiveness of real-time 3D reconstruction methods be assessed? This paper explores various approaches to the challenge of live 3D reconstruction from typical point cloud data. It first introduces some common data flow patterns that characterize virtual reality applications and shows that achieving high-speed data transmission and efficient data compression is critical to maintaining visual continuity and ensuring a satisfactory user experience. The paper thus introduces the concept of saliency-driven compression/reconstruction and compares it with alternative state-of-the-art approaches.