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This study was aimed at comparing the mechanical parameters of ceramics made using the addition and subtraction technique. A search was performed on four search engines on 5th April 2023. Quality assessment was performed using study type-specific scales. Where possible, a meta-analysis was performed. Data were extracted from four search engines: PubMed, PubMed Central, Embase, Web of Science, Scopus. The search strategy identified 686 potential articles. 19 papers were subject to qualitative analysis, and data from 11 papers were meta-analysed. The included studies were of high or medium quality. All included papers were in-vitro studies. No clinical trials were found in the literature. Ceramics made in the additive technology in terms of mechanical parameters can compete with ceramics made in the milling technology. There are no clinical studies yet that would indicate the use of this type of material for permanent restorations in patients. Studies presented in the literature vary greatly in terms of study design and reporting of results. The research did not receive external funding. • Ceramics manufactured additively is overall characterized by smaller flexural strength, but insignificant then the ones manufactured subtractively. • There is no significant difference between the type of ceramics in microhardness. However, there is a significant heterogeneity in both cases (in both meta-analyses). • This review describes many articles, all of which were about in-vitro research. There is a lack of research that would refer to the clinical usefulness of 3D printing in dentistry. [ABSTRACT FROM AUTHOR]

A general three-dimensional anisotropic model is proposed within the non-ordinary state-based peridynamic framework in this work. Three-dimensional peridynamic formulations for anisotropic solids are formulated, and two types of stress rate solutions, Green-Naghdi and Jaumann stress rate are implemented in this model, respectively. Moreover, the equivalent bond stress and corresponding equivalent bond strain are presented and calculated. The 3D-Hashin failure criterion is used among the numerical analysis of anisotropic materials through the equivalent bond strain. Various typical cases are performed by the proposed anisotropic peridynamic model and approach, including the numerical analyses of quasi-static deformation and dynamic fracture for anisotropic materials. The effectiveness and applicability of the proposed model are verified by precisely characterizing the quasi-static deformation and dynamic failure behavior. • A general three-dimensional anisotropic model within the NOSB-PD framework. • Green-Naghdi and Jaumann stress rate are implemented in this anisotropic model. • A 3D-Hashin failure criterion is employed through the equivalent bond strain. • Quasi-static deformation and dynamic failure behavior of anisotropic materials. [ABSTRACT FROM AUTHOR]

Objectives: To assess the surgical accuracy of 3D virtually planned orthognathic surgery among patients with and without cleft. Materials and methods: This retrospective cohort study included cleft and non-cleft patients with class III malocclusion who underwent bimaxillary surgery. CBCT scans were acquired before and immediately after surgery. 3D virtual surgical planning (VSP) was performed using CBCT and digitalized dentition data. All orthognathic surgeries were performed by the same surgeons using interocclusal splints. The primary outcome variable was surgical accuracy, defined as the difference between the planned and surgically achieved maxillary movements, quantified in six degrees of freedom. Analysis of covariance was used to test for intergroup differences in surgical accuracy after correcting for differences in the magnitude of planned surgical maxillary movements. Results: Twenty-eight cleft and 33 non-cleft patients were enrolled, with mean ages of 18.5 and 25.4 years, respectively (P=0.01). No significant gender difference was present between the groups (P=0.10). After adjustment for small differences in surgical movements, no significant differences in surgical accuracy were observed between cleft and non-cleft patients. Conclusion: The present study demonstrates that high surgical accuracy in maxillary movements can be achieved in both cleft and non-cleft patients using VSP and interocclusal splints. Clinical relevance: Orthognathic cases with cleft can be performed with 3D VSP to obtain a satisfactory surgical accuracy. [ABSTRACT FROM AUTHOR]

In this paper, the oscillatory properties and asymptotic behaviour of a third-order three-dimensional neutral system are discussed. Some sufficient conditions are obtained to ensure that all bounded positive solutions of the system are oscillatory or non-oscillatory. On the other hand, the non-oscillatory solutions either converge or diverge when t goes to infinity. A special technique is adopted to include all possible cases. The obtained results include illustrative examples. [ABSTRACT FROM AUTHOR]

The placenta mediates physiological exchange between the mother and the fetus. In placental mammals, all placentas are descended from a single common ancestor and functions are conserved across species; however, the placenta exhibits radical structural diversity. The selective pressures behind this structural diversity are poorly understood. Traditionally, placental structures have largely been investigated by grouping them into qualitative categories. Assessing the placenta on this basis could be problematic when inferring the relative "efficiency" of a placental configuration to transfer nutrients from mother to fetus. We argue that only by considering placentas as three-dimensional (3D) biological structures, integrated across scales, can the evolutionary questions behind their enormous structural diversity be quantitatively determined. We review the current state of placental evolution from a structural perspective, detail where 3D imaging and computational modeling have been used to gain insight into placental function, and outline an experimental roadmap to answer evolutionary questions from a multiscale 3D structural perspective. Our approach aims to shed light on placental evolution, and can be transferred to evolutionary investigations in any organ system. [ABSTRACT FROM AUTHOR]

The active earth pressure of earth-retaining structures (ERSs) is highly dependent on rainfall infiltration. In prior studies, ERS stability was primarily explored based on backfills under unsaturated steady flows or those that were saturated or dry while neglecting the time-dependent properties of the rainfall infiltration procedure. Accordingly, this study assessed the stability of a three-dimensional (3D) unsaturated ERS under diverse modes of rainfall infiltration by exploiting the upper bound theorem of limit analysis. A modified Green–Ampt model was adopted to consider the development of the wetting front; thereafter, an energy equilibrium equation was built to analytically derive the active earth pressure. The effects of the wall friction angle, ERS 3D geometrical characteristics, rainfall infiltration intensity and duration, and rainfall patterns on the active earth pressure coefficient were investigated. According to the results, the wall friction angle and 3D geometrical characteristics lead to a smaller active earth pressure and a superior stability state. The matric suction is a direct determinant of the active earth pressure and stability of the ERS; these exert major effects on the infiltration rate of rainfall into the soil. Furthermore, the rainfall pattern and intensity also have significant impacts on the active earth pressure and the development of the wetting front. [ABSTRACT FROM AUTHOR]

The vertebral heart scale (VHS) is the most common method used for the objective evaluation of heart size, however, VHS cannot evaluate the entire heart area. This retrospective study aimed to evaluate the development and feasibility of vertebral heart area ratio (VHAR=heart area/the fourth thoracic vertebra [T4] body area) as a new cardiac measurement method. A total of 125 dogs considered without clinical heart abnormalities in the pre-anesthetic examination, measurements of the VHS and VHAR using thoracic radiography were compared with computed tomography measurements of the vertebral cardiac volume ratio (VCVR=cardiac volume/T4 body volume) and investigate whether the VHAR values differed between observers. The mean cardiac and T4 body volumes were 116.99 ± 108.07 cm³ and 0.92 ± 0.91 cm³, respectively. The mean values of observers 1 and 2 were 9.9 ± 0.7 v (VHS), 42.64 ± 27.94 cm² (heart area), and 1.37 ± 0.96 cm² (T4 body area). Intraclass coefficients were the highest for the heart area, followed by the T4 body area and VHS. The VHAR showed a moderate correlation with VHS in observers 1 (r=0.671) and 2 (r=0.633). The VCVR showed a more positive correlation with VHAR (r=0.573) than with VHS (r=0.426). These results indicated that VHAR could be used as a complement to VHS for heart size measurement, and the high degree of observer agreement for the measurements indicated the measurement reproducibility of VHAR. [ABSTRACT FROM AUTHOR]

Skeletal stability after orthognathic surgery is essential for positive treatment outcome. This study evaluated the stability of osteotomy segments after surgery-first bimaxillary surgery for class III asymmetry. Seventy adults with class III asymmetry consecutively corrected through surgery-first Le Fort I and bilateral sagittal split osteotomies were investigated. Cone-beam computed tomography before treatment (T0), 1-week after surgery (T1), and after all treatment (T2, ≥1-year after surgery) was used to assess surgical movement (T0 to T1) and skeletal stability (T1 to T2) regarding the translation and rotation of the maxillary, mandibular distal, and proximal segments. At T1, the maxillary segment had moved forward and upward, turned to the deviated side, and rotated downward (all P < 0.01). The distal segment of mandible had moved forward and upward and rotated upward (all P < 0.001). The deviated proximal segment had moved upward, tilted to the opposite side, and rotated upward (all P < 0.001). The opposite proximal segment had moved upward and tilted to the deviated side (both P < 0.01). At T2, significant relapse occurred in the mandible. The distal segment moved forward and upward and rotated upward (all P < 0.001). The deviated proximal segment moved upward, tilted to the opposite side, and rotated upward (all P < 0.001). The opposite proximal segment moved upward and tilted to the deviated side (both P < 0.01). Clinically significant relapse of class III asymmetry was discovered on the mandibular distal and opposite proximal segments. [ABSTRACT FROM AUTHOR]

A real-time 3D Telemedicine system – leveraging Microsoft's Holoportation™ communication technology – enabled an international multidisciplinary team meeting (MDT) to consult with complex reconstructive patients before, during, and after an overseas surgical collaboration. A proof-of-concept international 3D MDT clinic took place in November 2022, between the Canniesburn Plastic Surgery Unit, UK, and the National Reconstructive Plastic Surgery and Burns Centre, Korle Bu Teaching Hospital, Ghana. The 3D system was utilised 1) previsit to assess patients and enable logistical planning, 2) on-site in Ghana to further allow patients to see themselves and proposed operations in 3D, and 3) post visit to debrief the team and patients. Four Ghana patients were followed through their patient journey (mandibular ameloblastoma, sarcoma thigh, maxillary tumour, sarcoma back). Thirteen participants (four patients, four Ghana clinicians, and five UK clinicians) completed feedback on the 3D MDT. Outcome measures were rated highly with satisfaction 84.31/100, perceived benefit 4.54/5, overall quality 127.3/147 (Telehealth Usability Questionnaire), and usability 83.2/100 (System Usability Scale). These data show close alignment with that previously published on high-income countries. This novel technology has the potential to enhance the delivery of overseas surgical visits to low-to-middle-income countries, by improving planning, informed discussion with patients, expert consensus on complex cases, and fostering engagement with professionals who may be thousands of miles away. This is the first demonstration that real-time 3D Telemedicine can both work, and enhance care within an international MDT clinic, and may thus enable change in the approach to overseas surgical collaborations. [Display omitted] [ABSTRACT FROM AUTHOR]

4D printing is an innovative digital manufacturing technology that originated by adding a fourth dimension, i.e., time, to pre-existing 3D technology or additive manufacturing (AM). AM is a fast-growing technology used in many fields, which develops accurate 3D objects based on models designed by computers. Dentistry is one such field in which 3D technology is used for manufacturing objects in periodontics (scaffolds, local drug-delivering agents, augmentation of ridges), implants, prosthodontics (partial and complete dentures, obturators), oral surgery for reconstructing jaw, and orthodontics. Dynamism is a vital property needed for the survival of materials used in the oral cavity since the oral cavity is constantly subjected to various insults. 4D printing technology has overcome the disadvantages of 3D printing technology, i.e., it cannot create dynamic objects. Therefore, constant knowledge of 4D technology is required. 3D printing technology has shortcomings, which are discussed in this review. This review summaries various printing technologies, materials used, stimuli, and potential applications of 4D technology in dentistry. [ABSTRACT FROM AUTHOR]

Background: Cranioplasty is a routine neurosurgery treatment used to correct cranial vault abnormalities. Utilization of 3D printing technology in the field of cranioplasty involving the reconstruction of cranial defects emerged as an advanced possibility of anatomical reshaping. The transformative impact of patient-specific 3D printed implants, focuses on their remarkable accuracy, customization capabilities, and enhanced biocompatibility. Methods: The precise adaptation of implants to patient-specific anatomies, even in complex cases we presented, result in improved aesthetic outcomes and reduced surgical complications. The ability to create highly customized implants addresses the functional aspects of cranial defects and considers the psychological impact on patients. Results: By combining technological innovation with personalized patient care, 3D printed cranioplasty emerges as a transformative avenue in cranial reconstruction, ultimately redefining the standards of success in neurosurgery. Conclusion: 3D printing allows an excellent cranioplasty cosmesis achieved at a reasonable price without sacrificing patient outcomes. Wider implementation of this strategy can lead to significant healthcare cost savings. [ABSTRACT FROM AUTHOR]

Background: A debate exists on whether the size of temporal bone pneumatization is a cause or consequence of otitis media (a global disease burden). However, a normal middle-ear mucosa is a prerequisite for normal temporal bone pneumatization. This study investigated the size of temporal bone pneumatization with age and the normal distribution of air cell volume in different stages of human growth postnatally. Materials and methods: A three-dimensional computer-based volumetric-rendering technique was performed bilaterally on 248 head/brain and internal acoustic meatus computed tomography images of slice thickness ≤ 0.6 mm consisting of 133 males and 115 females with age range 0-35 years. Results: The average volume of infant (0-2 years) pneumatization was 1920 mm3 with an expected rapid increase to about 4510 mm3 in childhood (6-9 years). The result also showed a significant increase (p < 0.001) in the volume of air cells up to the young adult stage I (19-25 years), followed by a significant decline in young adult stage II (26-35 years). However, the females were observed to experience an earlier increase than males. Also, population differences were observed as the Black South African population group showed a higher increase in volume with age than the White and Indian South African population groups, though the volumes of the latter increased up to young adult stage II. Conclusions: This study concludes that the pneumatization of a healthy temporal bone is expected to continue a linear increase up until at least adult stage I. Termination of temporal bone pneumatization in an individual before this stage could signify pathologic involvement of the middle ear during childhood. [ABSTRACT FROM AUTHOR]

Limited research has been conducted on the spatial ability of veterinary students and how this is evaluated within anatomy assessments. This study describes the creation and evaluation of a split design multiple‐choice question (MCQ) assessment (totaling 30 questions divided into 15 non‐spatial MCQs and 15 spatial MCQs). Two cohorts were tested, one cohort received a 2D teaching method in the academic year 2014/15 (male = 15/108, female 93/108), and the second a 3D teaching method in the academic year 2015/16 (male 14/98, female 84/98). The evaluation of the MCQ demonstrated strong reliability (KR‐20 = 0.71 2D and 0.63 3D) meaning the MCQ consistently tests the same construct. Factor analysis of the MCQ provides evidence of validity of the split design of the assessment (RR = 1.11, p = 0.013). Neither cohort outperformed on the non‐spatial questions (p > 0.05), however, the 3D cohort performed statistically significantly higher on the spatial questions (p = 0.013). The results of this research support the design of a new anatomy assessment aimed at testing both anatomy knowledge and the problem‐solving aspects of anatomical spatial ability. Furthermore, a 3D teaching method was shown to increase students' performance on anatomy questions testing spatial ability. [ABSTRACT FROM AUTHOR]

Investigating interindividual variability is a major field of interest in neuroscience. The entorhinal cortex (EC) is essential for memory and affected early in the progression of Alzheimer's disease (AD). We combined histology ground‐truth data with ultrahigh‐resolution 7T ex vivo MRI to analyze EC interindividual variability in 3D. Further, we characterized (1) entorhinal shape as a whole, (2) entorhinal subfield range and midpoints, and (3) subfield architectural location and tau burden derived from 3D probability maps. Our results indicated that EC shape varied but was not related to demographic or disease factors at this preclinical stage. The medial intermediate subfield showed the highest degree of location variability in the probability maps. However, individual subfields did not display the same level of variability across dimensions and outcome measure, each providing a different perspective. For example, the olfactory subfield showed low variability in midpoint location in the superior–inferior dimension but high variability in anterior–posterior, and the subfield entorhinal intermediate showed a large variability in volumetric measures but a low variability in location derived from the 3D probability maps. These findings suggest that interindividual variability within the entorhinal subfields requires a 3D approach incorporating multiple outcome measures. This study provides 3D probability maps of the individual entorhinal subfields and respective tau pathology in the preclinical stage (Braak I and II) of AD. These probability maps illustrate the subfield average and may serve as a checkpoint for future modeling. [ABSTRACT FROM AUTHOR]

Drone imagery has the potential to enrich urban planning and historic preservation, especially where it converges with the growing creation and use of 3D models in the context of cities and metro regions. Nevertheless, the widespread adoption of drones in these fields faces limitations, and there is a shortage of research addressing this issue. Therefore, we have conducted a systematic literature review of articles published between 2002 and 2022 drawing from reputable academic repositories, including Science Direct, Web of Science, and China National Knowledge Infrastructure (CNKI), to identify current gaps in the existing research on the application of UAVs to the creation of 3D models in the contexts of urban planning and historic preservation. Our findings indicate five research shortcomings for 3D city modeling: limited participation of planning experts, research focus imbalance, lack of usage for special scenarios, lack of integration with smart city planning, and limited interdisciplinary collaboration. In addition, this study acknowledges current limitations around UAV applications and discusses possible countermeasures along with future prospects. [ABSTRACT FROM AUTHOR]

Introduction: Left ventricular (LV) strains are measures of deformation that reflect LV function quantifying the rate of LV contraction, providing information in three directions in space: radial (RS), longitudinal (LS) and circumferential directions (CS). The LV moves around its longitudinal axis in a special movement called LV rotational mechanics. The present study aimed to assess associations between three-dimensional speckle-tracking echocardiography (3DSTE)-derived LV rotational mechanics and LV strains in healthy adult subjects. Methods: The present study consisted of 174 healthy adults (mean age: 32.8 ± 12.2 years, 79 males). Complete two-dimensional Doppler echocardiography and 3DSTE were performed in all subjects. Results: While LV-gRS and LV-gLS did not show associations with increased basal LV rotation, the lowest LV-gCS was seen in the presence of the highest LV basal rotation. An increase in basal LV rotation and consequential LV twist were not associated with apical LV rotation. While LV-gLS was not associated with the increase in apical LV rotation, LV-gRS and LV-gCS showed a trend towards increasing values. An increase in LV-gRS was associated with an increasing trend towards apical LV rotation, LV twist and LV-gCS and the preservation of basal LV rotation. LV-gLS also increased but only up to a certain value. An increase in LV-gCS was associated with a tendency towards a decrease in basal LV rotation and a tendency towards an increase in LV-gRS and LV-gLS. The highest LV-gCS was associated with the highest apical LV rotation and LV twist. The highest apical LV rotation, LV twist and LV-gCS were seen in the presence of the highest LV-gLS, while basal LV rotation and LV-gRS were not associated with increasing LV-gLS. Conclusions: Basal LV rotation has been shown to have an inverse relationship with LV-gCS, but without being related to LV-gRS and LV-gLS, while apical LV rotation is associated with LV strains in all directions, but to a different extent, suggesting a complex relationship between LV rotational mechanics and LV strains in healthy adults. [ABSTRACT FROM AUTHOR]

This feasibility study aims to explore the use of three-dimensional virtual surgical planning to preoperatively determine the need for reconstructive surgery following resection of an extremity soft-tissue sarcoma. As flap reconstruction is performed more often in advanced disease, we hypothesized that tumor volume would be larger in the group of patients that had undergone flap reconstruction. All patients that were treated by surgical resection for an extremity soft-tissue sarcoma between 1 January 2016 and 1 October 2019 in the University Medical Center Groningen were included retrospectively. Three-dimensional models were created using the diagnostic magnetic resonance scan. Tumor volume was calculated for all patients. Three-dimensional tumor volume was 107.8 (349.1) mL in the group of patients that had undergone primary closure and 29.4 (47.4) mL in the group of patients in which a flap reconstruction was performed, p = 0.004. Three-dimensional tumor volume was 76.1 (295.3) mL in the group of patients with a complication following ESTS treatment, versus 57.0 (132.4) mL in patients with an uncomplicated course following ESTS treatment, p = 0.311. Patients who had undergone flap reconstruction had smaller tumor volumes compared to those in the group of patients treated by primary closure. Furthermore, a larger tumor volume did not result in complications for patients undergoing ESTS treatment. Therefore, tumor volume does not seem to influence the need for reconstruction. Despite the capability of three-dimensional virtual surgical planning to measure tumor volume, we do not recommend its utilization in the multidisciplinary extremity soft-tissue sarcoma treatment, considering the findings of the study. [ABSTRACT FROM AUTHOR]

• Study on impact mesoscopic deformation characteristics of porous brittle materials. • Study on mesoscopic evolution mechanism of porous brittle materials containing micro-pores. • The 3D- LPSMR is used for calculation. Due to manufacturing, processing, etc., pores are flaws in a variety of brittle materials that can affect the material's impact dynamics properties. Studying the influence of pores and other defects on impact mesoscopic deformation characteristics can further utilize the beneficial functions of pores for engineering applications. Through the use of a 3D lattice point spring model with rotational degrees of freedom (3D-LSMR) that can precisely computationally simulate the fracture evolution mechanism of brittle materials, this paper reveals the mesoscopic deformation properties of spherical pores in brittle materials under impact loading. Under impact loading, pore collapse and shear cracking due to spherical pores can generate stress relaxation. The stress relaxation can evolve the shock-wave into a dual-wave structure of elastic wave (EW) and deformation wave (DW) in samples containing many spherical pores. The calculation results show that the porosity in the samples is an important factor influencing the Hugoniot elastic limit (HEL) of brittle materials. The impact velocity, porosity and material parameter variation factors is the key in influencing the propagation velocity of DWs. The results of the impact mesoscopic deformation characteristics obtained from the study are useful for the topology optimization of porous and brittle materials. [ABSTRACT FROM AUTHOR]

Purpose: Mismatch between partial imported prostheses and Chinese anatomy affects the clinical outcome of the procedure. The purpose of this study was to measure the anatomical dimensions of Chinese distal femurs to provide guidance for the design of more compatible distal femoral prostheses. Methods: A total of 406 healthy distal femurs were reconstructed and measured. Consistency of these measurements and differences in sides, gender, and populations were examined. Parameter correlations were analyzed, and pairs with strong correlations underwent linear regression analysis. The design of distal femoral prostheses was referenced from the results of K-means and hierarchical clustering analysis. Results: Ten parameters were measured, including the trans-epicondylar axis, width of the distal femur (ML), anteroposterior diameter of the distal femur (AP), etc. The intra-class correlation coefficient ranged from 0.795 to 0.999 for intra-observer consistency, and from 0.796 to 0.998 for inter-observer consistency. Males exhibited significantly larger parameters than females, except for the posterior condylar angle (all P values < 0.05). Compared to other populations, substantial differences were observed for most parameters, such as ML, AP, width of lateral femoral condyle, etc. (all P values < 0.05). Clustering analysis suggested that distal femoral prostheses should include at least five sizes to adequately accommodate the sampled population. ML sizes for males were 68, 70, 83, 73, and 89 mm, and for females 64, 65, 71, 67, and 77 mm. AP sizes for males were 56, 60, 60, 64, and 64 mm, and for females 48, 52, 54, 57, and 58 mm. Conclusions: Chinese distal femur morphology, as analyzed using 3D techniques, varies significantly between genders and when compared with international data. For improved patient fit, the creation of five or more distal femur prostheses, diversified by gender and size and informed by the associated morphological parameters, is recommended. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Study Design. A prospective cohort study. Objective. Detail typical three-dimensional segmental deformities and their rates of change that occur within developing adolescent idiopathic scoliosis (AIS) spines over multiple timepoints. Summary of Background Data. AIS is a potentially progressive deforming condition that occurs in three dimensions of the scoliotic spine during periods of growth. However, there remains a gap for multiple timepoint segmental deformity analysis in AIS cohorts during development. Materials and Methods. Thirty-six female patients with Lenke 1 AIS curves underwent two to six sequential magnetic resonance images. Scans were reformatted to produce images in orthogonal dimensions. Wedging angles and rotatory values were measured for segmental elements within the major curve. Two-tailed, paired t tests compared morphologic differences between sequential scans. Rates of change were calculated for variables given the actual time between successive scans. Pearson correlation coefficients were determined for multidimensional deformity measurements. Results. Vertebral bodies were typically coronally convexly wedged, locally lordotic, convexly axially rotated, and demonstrated evidence of local mechanical torsion. Between the first and final scans, apical measures of coronal wedging and axial rotation were all greater in both vertebral and intervertebral disk morphology than nonapical regions (all reaching differences where P<0.05). No measures of sagittal deformity demonstrated a statistically significant change between scans. Cross-planar correlations were predominantly apparent between coronal and axial planes, with sagittal plane parameters rarely correlating across dimensions. Rates of segmental deformity changes between earlier scans were characterized by coronal plane convex wedging and convexly directed axial rotation. The major locally lordotic deformity changes that did occur in the sagittal plane were static between scans. Conclusions. This novel investigation documented a threedimensional characterization of segmental elements of the growing AIS spine and reported these changes across multiple timepoints. Segmental elements are typically deformed from initial presentation, and subsequent changes occur in separate orthogonal planes at unique times. [ABSTRACT FROM AUTHOR]

Objective To explore the association between arch morphology and sprint performance in children, utilizing arch volume and arch index to assess arch development, and comparing and analyzing its relationship with athletic capability. Methods A total of 640 primary and secondary school students (324 boys and 316 girls) aged between 7 to 15 years were recruited from Chongqing Municipality. Foot arch index and arch volume were measured by "Foot Secret 3D Foot Plantar Scanner". Performance of 50-meter sprint was assessed. The participants were stratified into 6 groups based upon gender and age: boys aged 7-9 years (n=93), girls aged 7-9 years (n=103), boys aged 10-12 years (n=116), girls aged 10-12 years (n=112), boys aged 13-15 years (n=115) and girls aged 13-15 years (n=101). The correlations between arch index, arch volume and athletic performance were examined. Results In the age group of 7-9 years, the comparisons of both the left and right foot's weight-bearing arch index and the non-weight-bearing arch index between boys and girls showed no statistical significance (P>0.05). However, except for the comparisons of the left foot's weight-bearing arch volume and non-weight-bearing arch volume in the 7-9 year-old girls group, which showed no statistical significance (P>0.05), the following comparisons indicated a weak correlation with the 50-meter sprint performance and were statistically significant(P>0.05): the left foot's weight-bearing arch volume, the left foot's non-weight-bearing arch volume, the right foot's weight-bearing arch volume, and the right foot's non-weight-bearing arch volume in the 7-9 year-old boys group (r=-0.301, r=-0.294, r=-0. 295, r=-0.207), and the right foot's weight-bearing arch volume and non-weight-bearing arch volume in the 7-9 year-old girls group (r=-0.279, r=-0.278). In the 10-12 years age group, the comparisons of the right foot's arch index-both weight-bearing and non-weight-bearing-with the 50-meter sprint performance in the 10-12 year-old girls group showed a weak correlation (r=0.250, r=0.243) and were statistically significant (P < 0.05). However, the comparisons of the left foot's weight-bearing arch index, the left foot's non-weight-bearing arch index, the right foot's weight-bearing arch index, and the right foot's non-weight-bearing arch index in both the 10-12 year-old boys and girls groups showed no statistical significance (P>0.05). Moreover, except for the left foot's weight-bearing arch volume and non-weight-bearing arch volume in the 10-12 year-old girls group, which showed no statistical significance (P>0.05), the following comparisons indicated a weak correlation with the 50-meter sprint performance and were statistically significant: the left foot's weight-bearing arch volume, the left foot's non-weight-bearing arch volume, the right foot's weight-bearing arch volume, and the right foot's non-weight-bearing arch volume in the 10-12 year-old boys group (r=-0.273, r=-0.224, r=-0.236, r=-0.273), and the right foot's weight-bearing arch volume and non-weight-bearing arch volume in the 10-12 year-old girls group (r=-0.224, r=-0.211). In the 13-15 years age group, the comparisons of the left and right foot's arch index-both weight-bearing and non-weight-bearing-in the 13-15 year-old boys and girls groups with the 50-meter sprint performance showed no statistical significance (P>0.05). However, except for the non-weight-bearing arch volumes of the left and right feet in the 13-15 year-old girls group, which showed a weak correlation with the 50-meter sprint performance (r=-0.233, r=-0.225) and were statistically significant (P < 0.05), the comparisons of the left foot's weight-bearing arch volume, the left foot's non-weight-bearing arch volume, the right foot's weight-bearing arch volume, and the right foot's non-weight-bearing arch volume in the 13-15 year-old boys group, as well as the left foot's weight-bearing arch volume and the right foot's weight-bearing arch volume in the 13-15 year-old girls group, showed no statistical significance (P>0.05). Conclusions As a three-dimensional parameter, arch volume not only accurately depicts the development of foot arch but also serves as a reliable indicator for assessing motor capabilities in children. [ABSTRACT FROM AUTHOR]

Posterior glenoid bone loss is frequently observed in patients with osteoarthritis undergoing reverse total shoulder arthroplasty. Glenoid bone loss can reduce the baseplate back support area and the number of screws for fixation. The purpose of this study is to determine how initial baseplate fixation is affected by biomechanical factors introduced by glenoid bone loss such as reduced baseplate back support area and reduced screw number using three-dimensional finite element analysis. Computerized tomography images of a healthy shoulder were selected and segmented to obtain the solid geometry. Solid models were generated with 100%, 75%, 67%, 50%, and 25% glenoid baseplate back support. With these geometries, two groups of finite element models were then built. In the bone loss areas, screws were maintained in one group of models but were removed in the other group of models. 750N compressive loading was applied along the direction parallel to the scapula axis. Maximum von Mises stress and maximum micromotion between the bone and implant were recorded and evaluated for each glenoid bone model. In the group of models where all screws remained in place, the maximum stress and maximum micromotion between the bone and implant exhibited minimal variation. The maximum stresses were 21.10MPa and the maximum micromotions were between 2-3 μm. However, in the group of models removing screws in the bone loss areas, maximum stress increased from 20MPa to 45MPa and maximum micromotion increased from 2 μm to 85 μm as the backside support area decreased from 100% to 25%. In conclusion, this three-dimensional finite element analysis study demonstrates that initial fixation can be achieved with approximately 1/3 posterior glenoid bone deficiency even without screw placement in the area of bone loss. Glenoid bone loss affects baseplate fixation mainly by reducing the screw numbers for fixation. If screws can be placed in the bone loss area, the decreased baseplate back support area will not result in increased stresses or micromotion leading to baseplate failure. This study suggests that surgeons should consider applying screws to the bone loss area if the remaining bone is able to hold the screw. [ABSTRACT FROM AUTHOR]

In-house repositioning methods based on three-dimensional (3D)-printing technology and the use of pre-bent plates has been gaining popularity in orthognathic surgery. However, there remains room for further improvement in methods and investigations on clinical factors that affect accuracy. This single-centre, prospective study included 34 patients and aimed to evaluate the accuracy and factors influencing maxillary and mandibular repositioning using pre-bent locking plates. The plates were manually pre-bent on the 3D-printed models of the planned position, and their hole positions were scanned and reproduced intraoperatively with osteotomy guides. The accuracy of repositioning and plate-hole positioning was calculated in three axes with the set landmarks. The following clinical factors that affect repositioning accuracy were also verified: deviation of the plate-hole positioning, amount of planned movement, and amount of simulated bony interference. The median deviations of the repositioning and hole positioning between the preoperative plan and postoperative results were 0.26 mm and 0.23 mm, respectively, in the maxilla, and 0.69 mm and 0.36 mm, respectively, in the mandible, suggesting that the method was highly accurate, and the repositioning concept based on the plate hole and form matching was more effective in the maxilla. Results of the correlation test suggest that large amounts of bony interference and plate-hole positioning errors in the up/down direction could reduce mandibular repositioning accuracy. [ABSTRACT FROM AUTHOR]

Purpose: One of the most widely used benchmarks of lower-limb alignment is the mechanical axis (MA), which passes through the centers of the femoral head and the ankle in the weight-bearing position. However, where the MA passes through three-dimensionally (3D) is unclear. We investigated the MA in 3D (3D-MA) in knee osteoarthritis (OA) using upright computed tomography (CT). Materials and methods: This study included 66 varus OA knees from 38 patients [age 70.0 (64.8–77.0) years; median (interquartile range)]. The 3D-MA was determined using upright CT data and compared among Kellgren–Lawrence (KL) grades. Further, correlations between the 3D-MA and other parameters were evaluated. Results: The 3D-MA was located at 5.3 (1.3–14.4)% medially and 7.1 (0.7–15.3)% posteriorly on the tibial plateau in KL-1, and was translated medioposteriorly with increased KL grade. The 3D-MA in KL-3 [30.6 (22.6–42.6)% medially and 50.9 (45.8–80.2)% posteriorly] and KL-4 [56.7 (48.5–62.9)% medially and 92.3 (50.2–127.1)% posteriorly] was located extra-articularly. The mediolateral position of the 3D-MA correlated with the femorotibial angle [correlation coefficient (CC) = − 0.85, p < 0.001], and the anteroposterior position of the 3D-MA correlated with the knee flexion angle (CC = − 0.93, p < 0.001). Conclusion: Our analysis demonstrated that the 3D-MA in low-grade OA knees passes slightly medial and posterior to the knee center, and the 3D-MA is translated medioposteriorly with the progression of knee OA. Further, the 3D-MA is translated medially with varus progression and posteriorly with the progression of knee flexion contracture. [ABSTRACT FROM AUTHOR]

Imperfections in a 3D (three-dimensional) disc/plate gyroscopes are major factors that limit the gyroscope's sensitivity. Sources of imperfections may include nonuniform mass and stiffness distributions, non-homogeneity of damping distributions, axial misalignments, variations in radial distances, tilt-axis misalignment, et cetera. Geometric imperfections of a plate gyroscope will be covered in this paper. Firstly, we considered geometric imperfections based on the hypothesis of plane mid – surface of the plate in the form of outer rim imperfections of the plate. This type of imperfection arises due to imperfections in the plate's shape or mounting. Imperfections in the outer rim of the plate can cause fluctuations in the gyroscope's output, affecting its precession. This study also reveals that the outer rim radius imperfection causes the effect of "frequency splitting" for some harmonics. Secondly, we considered the effects of geometric imperfections of non-planar mid-surface on the plate/disc based on the theory of Mikhlin–Reissner shallow shells by introducing additional terms in the expression of the shear strain in comparison to the Novozhilov's theory of shells. Hence, the main effects of non-planar mid-surface of the plate are concentrated in the potential energy of elongations and shear strains. This type of imperfection may arise from assembly errors or external forces acting on the gyroscope and it may affect the gyroscope's output by impacting on its accuracy and stability. This paper is dedicated to modelling geometric imperfections that affect the accuracy of a 3D tuning plate gyroscope. Consequently, its main purpose is to derive equations of the motion and the associated forces that involve a geometrically imperfect plate gyroscope which vibrates both in-plane and out-of-plane with circumferential wave numbers m and respectively. [ABSTRACT FROM AUTHOR]

Background and Objectives: It would be important to know what happens to the volume and volume-based functional properties of one atrium if the size of the other atrium is larger or smaller than the average. Therefore, the present study aimed to perform three-dimensional speckle-tracking echocardiography (3DSTE)-derived quantification of left atrial (LA) and right atrial (RA) volumes and volume-based functional properties to examine these associations in healthy adults with mean and lower or higher than mean atrial volumes. Materials and Methods: The present study consisted of 179 healthy volunteers with a mean age of 32.3 ± 12.3 years (92 males). Three-dimensional speckle-tracking echocardiography-derived LA and RA volumes and volume-based functional properties were determined in all cases. Results: When different LA or RA volume groups were evaluated, both LA and RA showed the same pattern of volume changes in all phases of atrial function with higher LA or RA volumes. In case of low and mean LA volumes, RA volumes were higher compared to their LA counterpart. In case of mean and high RA volumes, RA volumes proved to be higher as well. In case of mean LA or RA volumes, differences between LA and RA stroke volumes (SVs) could not be detected, but all atrial emptying fractions (EFs) were lower for RA than for LA. Some differences were detected in counterpart LA/RA total, passive, and active atrial SVs and EFs values in the presence of lower/higher than mean LA/RA volume. Conclusions: In case of mean LA or RA volumes, RA volumes are higher compared to their LA counterpart, LA-SVs and RA-SVs are similar, but atrial EFs are lower for RA than for LA. If lower/higher than mean LA or RA volumes are present, some differences in patterns of changes in counterpart atrial volumes—SVs and EFs—could be detected. [ABSTRACT FROM AUTHOR]

This communication reports the joint effects of Thermal Diffusion and Diffusion Thermo on viscous and incompressible three-dimensional nanofluid flow towards a stretching sheet in connection to the influence of a magnetic field. In this study, nanofluid model is employed for the effects of thermophoresis and Brownian motion. Following that, similarity variables are chosen to turn the dimensional nonlinear system into dimensionless expressions and the resultant transformed equations are solved numerically using Finite Element method. Special emphasis has been given to the parameters of physical interest. These findings are visually presented through graphical representations, providing a clear and insightful understanding involved in this flow scenario. In addition, the final results are examined in light of past research and it is determined that they meet the convergence standards to an exceedingly satisfactory degree. The study's findings are beneficial for many technical and commercial endeavours. [ABSTRACT FROM AUTHOR]

This study compared the accuracy of traditional endodontic access to conservative access cavities prepared with or without novel nonrestrictive endodontic access guides by operators with different levels of clinical experience without visual aids, using a three‐dimensional volumetric accuracy analysis method. The accuracy of the preparations was analysed using a novel 3D volumetric analysis by calculating the intersection and volume of the actual cavities to the planned model cavities. The experienced operator significantly outperformed the inexperienced operator in the free hand groups, while accuracy of conservative access cavities prepared using the novel guides were comparable and significantly higher than the other groups (p < 0.05). The results demonstrated clinical experience enhanced endodontic preparations accuracy and that nonrestrictive guides achieve accurate conservative access cavities which are independent of the operator skill level. Additionally, the three‐dimensional volumetric analysis is a consistent and objective method to judge the accuracy of guided endodontic techniques. [ABSTRACT FROM AUTHOR]

Simple Summary: Due to the increasing incidence of early-stage lung cancer and the demand for less invasive surgeries, sublobar resections are rapidly increasing in the field of lung cancer surgery. Recently, three-dimensional imaging technology and software solutions that enable highly precise lung segmentectomy simulations have been developed. In this article, we review reports on recent three-dimensional technology and its application in lung cancer surgery, introduce precision lung segmentectomies performed at our facility, and discuss its limitations. In the future, more accurate recognition of anatomical structures between the pulmonary artery, vein, and bronchus using artificial intelligence technology, visualization of anatomical structures using immersive technology such as extended reality, and devices that can be used intraoperatively without obstructing the operative field will be developed. If these advancements are realized, we believe that further high-quality tailor-made sublobar resections for lung cancer will be possible. The clinical application of three-dimensional computed tomography (3D-CT) technology has rapidly expanded in the last decade and has been applied to lung cancer surgery. Two consecutive reports of large-scale prospective clinical trials from Japan and the United States have brought a paradigm shift in lung cancer surgery and may have led to a rapid increase in sublobar lung resections. Sublobar resection, especially segmentectomy, requires a more precise understanding of the anatomy than lobectomy, and preoperative 3D simulation and intraoperative navigation support it. The latest 3D simulation software packages are user-friendly. Therefore, in this narrative review, we focus on recent attempts to apply 3D imaging technologies, particularly in the sublobar resection of the lung, and review respective research and outcomes. Improvements in CT accuracy and the use of 3D technology have advanced lung segmental anatomy. Clinical applications have enabled the safe execution of complex sublobar resection through a minimally invasive approach, such as video-assisted thoracoscopic surgery and robotic surgery. However, currently, many facilities still render 3D images on two-dimensional monitors for usage. In the future, it will be challenging to further spread and advance intraoperative navigation through the application of 3D output technologies such as extended reality. [ABSTRACT FROM AUTHOR]

Epoxy (EP) is the preferred packaging materials used as a crucial component in power semiconductor devices. However, its low thermal conductivity (TC) always has negative impact in the heat dissipation of electronic devices. In this paper, we use hole-making method to prepare three-dimensional boron nitride ceramics-carbon (3D-BN-C) hybrids which are filled in EP matrix to improve the TC of the 3D-BN-C/EP composites. The results show that TC values of 3D-BN-C/EP composites are much superior to the BN/EP composite with random distribution of BN and 3D-BN/EP composite without carbon. The improved TC is mainly attributed to the high TC-3D skeleton structure and the low interface thermal resistance (R) due to the carbon connected with BN fillers. Infrared thermal images and Comsol simulation demonstrate that high TC 3D-BN-C/EP composite offers excellent heat dissipation capability of EP composites used as packing insulation materials. In addition, the dielectric loss of 3D-BN-C/EP composite still remains at a relative low level in a wide frequency range, exhibiting good insulation property and great potential to be used as high-performance packing insulation materials in electronic device applications. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was examining the accuracy of accelerometer-based portable navigation systems (HipAlign) when measuring leg length changes using two-dimensional (2D) and three-dimensional (3D) methods. Methods: Inclusion criteria were patients ≥ 20 years old with symptomatic hip disease who underwent primary total hip arthroplasty (THA) in the supine position using HipAlign between June 2019 and April 2020. The exclusion criteria were patients who underwent THA via a posterior approach. We examined correlations between the leg length change measurement with HipAlign and either 2D or 3D measurement. We performed a multivariate analysis to determine which factors may have influenced the absolute error results. Results: This study included 34 patients. The absolute error in leg length change between the HipAlign and 3D measurement (4.0 mm) was greater than the HipAlign and 2D measurement (1.7 mm). There were positive correlations between leg length change with HipAlign and 2D and 3D measurements. Male patients had larger errors with 2D measurement. No significant factors were identified for 3D measurement. Conclusion: HipAlign provided acceptable measurement accuracy for leg length changes. [ABSTRACT FROM AUTHOR]

Rotational angiography, often referred to as a "spin", is typically presented in 2D. Since rotational angiograms are composed of images acquired from multiple angles, we took advantage of this property to develop a method for converting any rotational angiogram into a 3 dimensional (3D) video. Our aim was to develop a low cost and easily distributable solution without requiring additional hardware or altering acquisition techniques. Six previously acquired rotational angiograms from our institution were imported using custom-written code and exported as anaglyph (red-cyan) videos. The resulting 3D videos convey anatomical depth that is not apparent from viewing the 2D images alone. Processing time was 1.3 ± 0.6 s (mean ± SD) per angiogram. The only associated cost was $10 for red-cyan 3D glasses. Using our software, any rotational angiogram with at least 0.3 frames per degree of rotation can be converted into 3D. Our solution is an inexpensive and rapid method for generating stereoscopic videos from existing angiograms. It does not require any additional hardware and is readily deployable in low-resource settings. Because the videos are in anaglyph format, they are viewable on any 2 dimensional (2D) display in the interventional suite or operating room, on a mobile device, or at home. [ABSTRACT FROM AUTHOR]

Advances in the development of pharmacological treatment in oral cancer require tumor models capable of simulating the complex biology of the tumor microenvironment. The spread of three-dimensional models has changed the scenery of in vitro cell culture techniques, contributing to translational oncology. Still, the full extent of their application in preclinical drug trials is yet to be understood. Therefore, the present scoping review protocol was established to screen the literature on using three-dimensional cell culture models in drug-testing assays in the context of oral cancer. This scoping review will be conducted based on the guidelines established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Review guidelines (PRISMA-ScR). We will search the PubMed/Medline, Web of Science, Scopus, and Embase databases, as well as the gray literature, including peer-reviewed research articles involving 3D models applied to drug-assessment assays in oral cancer published from 1 March 2013 until 1 March 2023. Data will be charted, and findings will be described according to the predetermined questions of interest. We will present these findings in a narrative manner. [ABSTRACT FROM AUTHOR]

The present work investigates the flow of a continuous, laminar, 3-D boundary-layer over a fixed wedge, where the outside free-stream flows are approximately approximated by a power of distances. The controlling partial differential equations are transformed into coupled nonlinear ordinary differential equations with the necessary boundary conditions using surface similarity transformations. These equations involve two physical variables: pressure gradient and shear-to-strain rate. The resulting equations are numerically solved by the implicit finite-difference scheme known as the Keller-box approach. The obtained results are compared with those reported in the literature for a few special cases. Our numerical results indicate that the flow zone is divided into two areas: near-field (close to the wedge surface) and far-field field (mostly controlled by inviscid flow). [ABSTRACT FROM AUTHOR]

Some resin polymers available for three-dimensional (3D) printing are slightly elastic, which may be advantageous when used for full crown coverage of the primary teeth. This study was performed to evaluate the mechanical properties of two types of 3D-printed resin crowns in terms of strength and surface characteristics. Polymer resins used for temporary crowns (TCs) and temporary flexible dentures (TFDs) were tested. Digitally designed crowns with different thicknesses (0.4 and 0.6 mm) were 3D-printed. Milled zirconia crowns were used as the control. The static and dynamic fracture loads of the crowns were measured. The crown surface was evaluated using scanning electron microscopy. The average strength did not differ between the types of crowns. The differences between the dynamic and static fracture loads were insignificant. In the TC group, thicker crowns showed lower strength both under static and dynamic loads. After thermomechanical loading, microcracks and dropouts of macrofillers were detected on the surface of all types of resin crowns. The deposition of abraded debris occurred more in the TFD group. The 3D-printed resin crowns were thought to endure biting forces in children. However, some limitations of the material itself should be improved for consideration as a new treatment option in pediatric dentistry. [ABSTRACT FROM AUTHOR]

Different arch structures may cause different foot function injuries. In the past, the arch structure and flexibility of the foot were often defined by the height of the arch, and there was no three-dimensional (3D) structure classification method. In order to form a more complete 3D description, we propose a new classification system of arch volume flexibility (AVF), and then use this new classification system to investigate the relationship between the AVF and arch index (AI), and the arch height flexibility (AHF) and AI, respectively. It is proposed to recruit 180 young male adults for the test. We obtained arch volume and AI through 3D scanning and obtained the navicular height through manual measurement. Based on these data, we calculated the AHF and the AVF. Using the quintile method, these arches are divided into very stiff, stiff, neutral, flexible, and very flexible. According to AI value, all arches were divided into cavus, rectus, and planus. The distribution of AVF was compared using χ2 goodness of fit test. The spearman correlation test was used to compare the AHF and AVF. A p < 0.05 indicates that the difference is statistically significant. All participants' plantar data was obtained through 3D scanning, but only 159 of them were complete, so only 318 feet had valid data. The left AHF is (21.23 ± 12.91) mm/kN, and the right AHF is (21.71 ± 12.69) mm/kN. The AVF of the left foot arch is (207.35 ± 118.28) mm3/kg, while the right one is (203.00 ± 117.92) mm3/kg, and the total AVF of the arch was (205.17 ± 117.94) mm3/kg. There was no statistical difference in the AVF between the left and right feet for the same participant (n = 159, p = 0.654). In cavus, the percentage of arch with AVF is 21.4% (very stiff), 21.4% (stiff), 14.3% (neutral), 7.1% (flexible), and 35.7% (very flexible). In rectus, the percentage of arch with AVF is 23.9% (very stiff), 19.6% (stiff), 14.7% (neutral), 24.5% (flexible), and 17.2% (very flexible). In planus, the percentage of arch with AVF is 14.9% (very stiff), 20.6% (stiff), 27.0% (neutral), 16.3% (flexible), and 21.3% (very flexible). Moreover, the correlation between AHF and AVF is not significant (p = 0.060). In cavus, rectus, and planus, different AVF accounts different percentage, but the difference is not statistically significant. AVF is evenly distributed in the arches of the feet at different heights. We further found the relationship between AHF and AVF is not significant. As a 3D index, AVF may be able to describe the flexibility of the arch more comprehensively than AHF. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Sickle cell anemia (SCA) is a hematological condition that involves the synthesis of sickle‑shaped, hemoglobin with a short lifespan. This study employed three‑dimensional (3D) scanning to pinpoint the most common arch form in a sample of Iraqi adults with SCA. MATERIALS AND METHODS: A cross‑sectional study included maxillary and mandibular casts of 50 patients (25 male and 25 female) with SCA and 50 participants in a control group (25 male and 25 female). The facio‑axial (FA) point was digitized on each tooth’s labial or buccal surface using SolidWorks® 2020 software. The dimensions of the arch were calculated using two proportional measures and four linear measurements. The dental arch form was determined using 3M templates, and the arches were categorized as square, ovoid, or tapered to establish the most‑common arch form. Chi‑square was used to compare arch form distribution, and an independent t‑test was used to calculate the difference between the control group and the SCA group. RESULTS: The tapered arch was the predominant form in SCA males and females for the maxilla and the mandible. The molar vertical distance (upper and lower) was significantly higher in males in the SCA group than in males in the control group. There was no significant difference between females in the SCA group and females in the control group. CONCLUSION: Most patients with SCA had tapered arches. Sagittal jaw dimensions in males with SCA were more affected by marrow hyperplasia. There was little if any to no effect on females with SCA. [ABSTRACT FROM AUTHOR]

Objectives: Facial asymmetry is a common problem seen in orthodontic clinics that may affect patient esthetics. In some instances, severe asymmetry that affects patient esthetics may cause psychological issues. An objective method is therefore required to help orthodontists identify asymmetry issues. Materials and methods: We used three-dimensional (3D) facial images and landmark-based anthropometric analysis to construct a 3D facial mask to evaluate asymmetry. The landmark coordinates were transformed using a symmetric 3D face model to evaluate the efficacy of this method. Patients with facial asymmetry were recruited to conduct mirror and overlap analysis to form color maps, which were used to verify the utility of the novel soft tissue landmark-based method. Results: The preliminary results demonstrated that the asymmetry evaluation method had a similar response rate compared to diagnosis using mirror and overlap 3D images, and could therefore identify 3D asymmetry problems. Conclusions: By using 3D facial scans and 3D anthropometric analysis, we developed a preliminary evaluation method that provides objective parameters to clinically evaluate patient facial asymmetry and aid in the diagnosis of asymmetric areas. Clinical relevance: This study presents a novel facial asymmetry diagnostic method that has the potential to aid clinical decisions during problem identification, treatment planning, and efficacy evaluation.

Interconnected pathways in 3D bioartificial organs are essential to retaining cell activity in thick functional 3D tissues. 3D bioprinting methods have been widely explored in biofabrication of functionally patterned tissues; however, these methods are costly and confined to thin tissue layers due to poor control of low-viscosity bioinks. Here, cell-laden hydrogels that could be precisely patterned via water-soluble gelatin templates are constructed by economical extrusion 3D printed plastic templates. Tortuous co-continuous plastic networks, designed based on triply periodic minimal surfaces (TPMS), serve as a sacrificial pattern to shape the secondary sacrificial gelatin templates. These templates are eventually used to form cell-encapsulated gelatin methacryloyl (GelMA) hydrogel scaffolds patterned with the complex interconnected pathways. The proposed fabrication process is compatible with photo-crosslinkable hydrogels wherein prepolymer casting enables incorporation of high cell populations with high viability. The cell-laden hydrogel constructs are characterized by robust mechanical behavior. In vivo studies demonstrate a superior cell ingrowth into the highly permeable constructs compared to the bulk hydrogels. Perfusable complex interconnected networks within cell-encapsulated hydrogels may assist in engineering thick and functional tissue constructs through the permeable internal channels for efficient cellular activities in vivo.

Inter-organelle interactions are a vital part of normal cellular function; however, these have proven difficult to quantify due to the range of scales encountered in cell biology and the throughput limitations of traditional imaging approaches. Here, we demonstrate that soft X-ray tomography (SXT) can be used to rapidly map ultrastructural reorganization and inter-organelle interactions in intact cells. SXT takes advantage of the naturally occurring, differential X-ray absorption of the carbon-rich compounds in each organelle. Specifically, we use SXT to map the spatiotemporal evolution of insulin vesicles and their co-localization and interaction with mitochondria in pancreatic β cells during insulin secretion and in response to different stimuli. We quantify changes in the morphology, biochemical composition, and relative position of mitochondria and insulin vesicles. These findings highlight the importance of a comprehensive and unbiased mapping at the mesoscale to characterize cell reorganization that would be difficult to detect with other existing methodologies.

Pterygium is an ocular surface disorder with high prevalence that can lead to vision impairment. As a pathological outgrowth of conjunctiva, pterygium involves neovascularization and chronic inflammation. Here, we developed a 3D multicellular in vitro pterygium model using a digital light processing (DLP)-based 3D bioprinting platform with human conjunctival stem cells (hCjSCs). A novel feeder-free culture system was adopted and efficiently expanded the primary hCjSCs with homogeneity, stemness and differentiation potency. The DLP-based 3D bioprinting method was able to fabricate hydrogel scaffolds that support the viability and biological integrity of the encapsulated hCjSCs. The bioprinted 3D pterygium model consisted of hCjSCs, immune cells, and vascular cells to recapitulate the disease microenvironment. Transcriptomic analysis using RNA sequencing (RNA-seq) identified a distinct profile correlated to inflammation response, angiogenesis, and epithelial mesenchymal transition in the bioprinted 3D pterygium model. In addition, the pterygium signatures and disease relevance of the bioprinted model were validated with the public RNA-seq data from patient-derived pterygium tissues. By integrating the stem cell technology with 3D bioprinting, this is the first reported 3D in vitro disease model for pterygium that can be utilized for future studies towards personalized medicine and drug screening.

Mapping the localization of multiple proteins in their native three-dimensional (3D) context would be useful across many areas of biomedicine, but multiplexed fluorescence imaging has limited intrinsic multiplexing capability, and most methods for increasing multiplexity can only be applied to thin samples (

Abnormal tau inclusions are hallmarks of Alzheimer's disease and predictors of clinical decline. Several tau PET tracers are available for neurodegenerative disease research, opening avenues for molecular diagnosis in vivo. However, few have been approved for clinical use. Understanding the neurobiological basis of PET signal validation remains problematic because it requires a large-scale, voxel-to-voxel correlation between PET and (immuno) histological signals. Large dimensionality of whole human brains, tissue deformation impacting co-registration, and computing requirements to process terabytes of information preclude proper validation. We developed a computational pipeline to identify and segment particles of interest in billion-pixel digital pathology images to generate quantitative, 3D density maps. The proposed convolutional neural network for immunohistochemistry samples, IHCNet, is at the pipeline's core. We have successfully processed and immunostained over 500 slides from two whole human brains with three phospho-tau antibodies (AT100, AT8, and MC1), spanning several terabytes of images. Our artificial neural network estimated tau inclusion from brain images, which performs with ROC AUC of 0.87, 0.85, and 0.91 for AT100, AT8, and MC1, respectively. Introspection studies further assessed the ability of our trained model to learn tau-related features. We present an end-to-end pipeline to create terabytes-large 3D tau inclusion density maps co-registered to MRI as a means to facilitate validation of PET tracers.

The protocol describes step-by-step sample preparation, data acquisition, and segmentation of cellular organelles with soft X-ray tomography. It is designed for microscopes built to perform full-rotation data acquisition on specimens in cylindrical sample holders, such as the XM-2 microscope at the Advanced Light Source, LBNL; however, it might be generalized for similar sample holder designs for both synchrotron and table-top microscopes. For complete details on the use and execution of this profile, please refer to Loconte et al. (2021).

Ideal three-dimensional imaging of complex samples made up of micron-scale structures extending over mm to cm, such as biological tissues, requires both wide field of view and high resolution. For existing optics and detectors used for micro-CT (computed tomography) imaging, sub-micron pixel resolution can only be achieved for fields of view of

Epidermal basement membrane, a tightly packed network of extracellular matrix (ECM) components, is a source of physical, chemical, and biological factors required for the structural and functional homeostasis of the epidermis. Variations within the ECM create distinct environments, which can affect the property of cells in the basal layer of the epidermis and subsequently affect keratinocyte differentiation and stratification. Very little attention has been paid to mimicking basement membrane in organotypic cultures. In this study, using parameters outlined in a consensus on the quality standard of organotypic models suitable for dermatological research, we have evaluated three basement membrane substitutes. We compared fibronectin with three complex three-dimensional matrices: Matrigel, decellularized dermal fibroblast‒produced and ‒assembled ECM, and a dry human amniotic membrane. Our results suggest that Matrigel is not a suitable substrate for human epidermal equivalent culture, whereas the two other complex three-dimensional substitutes, decellularized dermal fibroblast‒produced and ‒assembled ECM and dry human amniotic membrane, were superior to single layer fibronectin coating. Human epidermal equivalents cultured on either decellularized dermal fibroblast‒produced and ‒assembled ECM or on dry human amniotic membrane generated hemidesmosomes, whereas those on fibronectin did not. In addition, human epidermal equivalent cultured on decellularized dermal fibroblast‒produced and ‒assembled ECM and on dry human amniotic membrane can be maintained in culture 4 days longer than human epidermal equivalent cultured on fibronectin without compromising the barrier function.

We develop a high-throughput technique to relate positions of individual cells to their three-dimensional (3D) imaging features with single-cell resolution. The technique is particularly suitable for nonadherent cells where existing spatial biology methodologies relating cell properties to their positions in a solid tissue do not apply. Our design consists of two parts, as follows: recording 3D cell images at high throughput (500 to 1,000 cells/s) using a custom 3D imaging flow cytometer (3D-IFC) and dispensing cells in a first-in-first-out (FIFO) manner using a robotic cell placement platform (CPP). To prevent errors due to violations of the FIFO principle, we invented a method that uses marker beads and DNA sequencing software to detect errors. Experiments with human cancer cell lines demonstrate the feasibility of mapping 3D side scattering and fluorescent images, as well as two-dimensional (2D) transmission images of cells to their locations on the membrane filter for around 100,000 cells in less than 10 min. While the current work uses our specially designed 3D imaging flow cytometer to produce 3D cell images, our methodology can support other imaging modalities. The technology and method form a bridge between single-cell image analysis and single-cell molecular analysis.

Abstract Past studies have focused on the importance of hydrological variables in analyzing landslide initiation condition. Even though precipitation is the main driver of shallow landslides and debris flows, use of only rainfall-based parameters has shown some limitations. Soil moisture has been used widely to improve threshold detection capabilities. Since soil moisture directly reflects the wetness status of the ground, it can be used to identify pore pressure fluctuations more effectively. This study used rainfall and soil moisture simultaneously to capture landslide initiation conditions in detail. Results showed that continued rainfall on the day of landslide leaded to a sudden increase in soil moisture, and that soil moisture increments (∆SM) were positive in 155 out of 170 landslide cases (91%). Two simple thresholds (daily precipitation over 40 mm, ∆SM over 0) and daily precipitation (P), Antecedent Precipitation Index (API), ∆SM-based three-dimensional threshold planes having 5%, 20% probability levels were applied and compared. With respect to false alarms (FA), P-based threshold was most effective among the single thresholds (FA ranging from 24 to 28 from September 2016 to December 2019 at five validation locations). Combining P- and ∆SM-based thresholds, FA reduced without compromising the detection accuracy (2 to 3 reduction in FA). Additionally combining three-dimensional threshold with 20% probability level, FA reduced significantly (ranging from 12 to 16), at the cost of two detection failures. These findings demonstrate the need for combining precipitation and soil moisture to determine landslide thresholds.

Peripheral neuropathy is known to be one of the most common neurological disorders. Despite the great diagnostic value of electroneuromyography and ultrasound, addressing the diagnostics and differential diagnostics of peripheral nerve diseases of different origin could be challenging. In recent years, magnetic resonance tomography has been increasingly used for evaluating cases of suspected or established peripheral neuropathy with excellent results. This manuscript mainly deals with the advantages and limitations of the aforementioned diagnostic instruments, technical considerations according to different anatomy of peripheral nerves, along with state-of-the-art technical decisions, frequently used magnetic resonance imaging sequences and their diagnostic value based on own observation, and recommendations for contrast enhancement use and different methods of fat suppression. Currently, there is practically no standardized description of normal magnetic resonance imaging features of peripheral nerves, as well as their changes in different diseases. The evaluation of images is mainly based on the radiologist experience, which obviously decreases method’s diagnostic value. Studies of large numbers involving healthy volunteers and patients with peripheral neuropathies of different origin are required to address this issue.