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Current advances and developments in automated mineralogy have made it a crucial key technology in the field of process mineralogy, allowing better understanding and connection between mineralogy and the beneficiation process. The latest developments in X‑ray micro-computed tomography (µCT) have shown a great potential to let it become the next-generation automated mineralogy technique. µCT’s main benefit lies in its capability to allow 3D monitoring of the internal structure of the ore sample at resolutions down to a few hundred nanometers, thus excluding the common stereological error in conventional 2D analysis. Driven by the technological and computational progress, µCT is constantly developing as an analysis tool and successively it will become an essential technique in the field of process mineralogy. This study aims to assess the potential application of µCT systems, for 3D ore characterization through relevant case studies. The opportunities and platforms that µCT 3D ore characterization provides for process design and simulation in mineral processing are presented.

Objectives: Assess the accuracy of 2D cephalograms reconstructed from 3D CBCT by comparing labial alveolar bone thickness over the most forward maxillary incisor (MFMI) in 2 dimensions vs 3 dimensions. Materials and Methods: Sixty cone-beam computed tomography (CBCT) images were coded, and 2-dimensional (2D) cephalograms were constructed using ray sum technique by using the entire volumetric data in the On demand 3DAPP software (version1.0.10.7s10;cybermed, korea). The 2D CBCT reconstructed images were analyzed using audax ceph 2d analysis software. The 2D and 3D MFMI crowns were located using (FH)-A-point line as the vertical reference line and alveolar bone labial to 3 points on the MFMI roots, using Frankfort horizontal FH line as a horizontal reference line, were measured. The 2D and 3D measurements were compared using paired t tests. A 5% significance level was used for all tests. Results: labial alveolar bone thickness over the 3 root points of MFMI and the MFMI distance to (FH)-A-point line were significantly greater in 2 dimensions than in 3 dimensions. Conclusions: Labial alveolar bone thickness over MFMI roots can be overestimated when evaluated using 2D reconstructed cephalograms compared with 3D evaluation. Alveolar bone measurements over maxillary incisors were interfered by ANS in two dimensions.

The city growth and development with all the dynamics are currently going on quite rapidly demand, the provision of facilities and city infrastructure is getting better and more adequate. Urban infrastructure development, especially those related to waste management, is an urgent need in the context of efforts to prevent environmental pollutions. Several factors need to be considered to building infrastructure, one of which is the security factor. The safety factor is a major factor in the construction of the retaining wall. The purpose of this study is to investigate mechanical effects of soil retaining wall in the three types of designs of the landfills by 2D finite element analysis. The results could provide a reference for building to withstand the active lateral compressive forces of soil and water. The contribution of this study is sufficient for providing a functional strength of retaining walls. FEM (Finite Element Method) is a numerical method that is often used in analysing the compressive strength of retaining wall. In this study, 2D analysis is used to determine the compressive strength of the soil on the retaining wall of the landfill in Manokwari City. The retaining wall in this study is varied based on these three forms of the retaining wall. It is according to the literature and the three different finite element numbers based on the software. Ansys software is used to simulate the compressive strength of retaining walls against the ground. The results found were compared. The results obtained indicated that the geometry design 2 has a better safety value when compared to the others. This is reinforced by the results of the numerical calculations obtained, namely A2 = 29497.3 N/mm2, B2 = 42579.2 N/mm2, and C2 = 82138.8 N/mm2.

Due to the adverse impacts of hip fractures on patients’ lives, it is crucial to enhance the identification of people at high risk through accessible clinical techniques. Reconstructing the 3D geometry and BMD distribution of the proximal femur could be beneficial in enhancing hip fracture risk predictions; however, it is associated with a high computational burden. It is also not clear whether it provides a better performance than 2D model analysis. Therefore, the purpose of this study was to compare the 2D and 3D model reconstruction’s ability to predict hip fracture risk in a clinical population of patients. The DXA scans and CT scans of 16 cadaveric femurs were used to create training sets for the 2D and 3D model reconstruction based on statistical shape and appearance modeling. Subsequently, these methods were used to predict the risk of sustaining a hip fracture in a clinical population of 150 subjects (50 fractured, and 100 non-fractured) that were monitored for five years in the Canadian Multicentre Osteoporosis Study. 3D model reconstruction was able to improve the identification of patients who sustained a hip fracture more accurately than the standard clinical practice (by 40%). Also, the predictions from the 2D statistical model didn’t differ significantly from the 3D ones (p > 0.76). These results indicated that to enhance hip fracture risk prediction in clinical practice implementing 2D statistical modeling has comparable performance with lower associated computational load.

One of the most precise methods of tracking water movement and measuring moisture content during hydration process is the usage of magnetic resonance imaging (MRI). In this study, the target samples were dried “Robusta” green coffee beans, and a series of images was acquired through an MRI system during the entire hydration process. Coffee beans were immersed in a glass bottle and were placed in a 35 mm diameter RF coil throughout the whole experiment. A set of 64 images with a field of view of 26 mm×26 mm was acquired. The hydration process of intact dried green coffee beans lasted for 360 min and image data sets were acquired every 10 min with an optimal GRE pulse sequence developed. The MR images were analyzed in 2D and 3D imaging spaces. The results of 2D analysis showed that the changes in water penetration depth inside coffee beans during the hydration process could be visualized. In addition, the results of 3D analysis presented a clearer understanding of the hydration process of dried coffee beans. This study showed that changes in water distribution and physical dimensions of coffee beans during the hydration process in 2D and 3D imaging spaces were meserable, without disturbing the process, by means of the MRI technique.

Objectives Common carotid artery (CCA) remodelling in the atherosclerosis process is an inherent necessary element that decreases the progress of significant lumen compromise. The present study used a semi-automated method to assess relationships of intima-media thickness (IMT), lumen diameter (LD) and inter-adventitial diameter (IAD) using ultrasound B-mode images of atherosclerotic carotid artery. Methods In the cross-sectional study, 120 male subjects (age range: 40–60 years) were classified into four research groups namely control, mild, moderate, and severe stenosis. The maximum near and far wall IMT, mean of both walls’ IMT and IAD, and also LD of the left CCA were extracted for all participants. Pearson correlation coefficient was utilized to investigate relationships of IMT, LD, and IAD. Results Results revealed that the maximum far and near wall IMT, mean of both walls’ IMT and IAD in the CCA were significantly different in stenosis patients and the control group ( p< 0.001). However, there were no significant differences among the four studied groups in terms of LD of CCA ( p = 0.65). There was a stronger correlation between mean of both walls’ IMT and IAD in comparison with mean far wall IMT and IAD ( p Conclusions Results indicated that changes of IAD in the left CCA were associated with carotid deformation, and thus it can be considered as a predictor of atherosclerosis process.

openaire: EC/H2020/633053/EU//EUROfusion Estimates for 2D distributions of electron temperature, Te, electron density, ne, and atomic deuterium density, n0, in the JET divertor volume have been inferred from deuterium Balmer line intensity ratios obtained from tomographic reconstructions of divertor camera measurements. This enables also investigation of ionization, Sion, and recombination, Srec, rates. The analysis shows a decrease of Te to 0.5-1.0 eV throughout the outer divertor during detachment in low-confinement (L-mode) plasmas. Simultaneously, the high-ne region and the n0 distribution in the outer divertor are observed to elongate and shift from the outer strike point towards the X-point. The observations are in qualitative agreement and follow the same sequence with modelling predictions of EDGE2D-EIRENE simulations of a density scan. While the method was found to provide good representation of the evolution of volumetric recombination during detachment, in agreement with the simulations, the movement of the ionization front upstream couldnot be followed due to lack of spatial overlap between the ionization region and the necessary emission distributions. Consequently, the representation of the ionization conditions and the particle balance in the detached outer divertor are compromised.

A medializing calcaneal osteotomy (MCO) is a surgical procedure frequently performed to correct an adult acquired flatfoot (AAFD) deformity. However, most studies are limited to a 2D analysis of 3D deformity. Therefore, the aim is to perform a 3D assessment of the hind- and midfoot alignment using a weightbearing CT (WBCT) preoperatively as well as postoperatively.Eighteen patients with a mean age of 49.4 years (range 18-67) were prospectively included in a pre-post-study design. A MCO was performed and a WBCT was obtained pre- and postoperative. Images were converted into 3D models to compute linear and angular measurements, respectively, in millimeters (mm) and degrees (°), based on previously reported landmarks of the hind- and midfoot alignment. A regression analysis was performed between the displacement of a MCO and the obtained postoperative correction.The mean 3D hindfoot angle improved significantly preoperative compared to postoperative (p 0.001). This appeared according to a linear relation with the amount of medial translation in a MCO (RThis study demonstrates an effective 3D correction of an AAFD by a MCO according to a linear relationship. The concomitant formula can be used to perform a preoperative planning. The novelty is the comparative 3D weightbearing CT assessment of both the computed hind- and midfoot alignment after a medializing calcaneus osteotomy. This could improve accuracy of the currently performed preoperative planning in clinical practice.

Generally, geotechnical construction works such as sheet pile walls are designed as plane-strain problems. In many practical cases, even if there is a need to consider 3D effects in the analysis, the designer tends to adopt conservative 2D analysis resulting in uneconomical design. This paper discusses a project in Dubai where sheet pile wall tie backed to anchor block was designed to retain 6.25 m height of compacted fill and account for future excavation considering 3D effect in anchor blocks. Anchor blocks were used to control the initial large deflections (> 50 mm) calculated in the sheet pile. Anchor blocks were analyzed considering 3D effects which resulted in increased pullout resistance (2.3 times) compared to assuming it as plane-strain problem. Simultaneously, numerical analyses were performed and an increase in pullout resistance (1.8 times) was noticed in 3D analysis compared to 2D analysis which confirms the importance of considering 3D effects in analyzing anchor blocks fetching subsequent optimization in anchor block design.

Soil-foundation interaction studies are quite useful to evaluate the behavior of shallow foundations, especially for flexible foundations. The soil and foundation parameters which affect the base pressure and settlement below shallow foundations includes the type of soil, soil compressibility, modulus of elasticity of soil, foundation dimensions, and thickness. Additionally, variation in loading parameters also have significant effect on the behavior of foundation. The foundation may behave as flexible or rigid foundation depending on the variation in loading. Hence, it would be interesting to understand the influence of variation in loading on behavior of shallow foundations. In this regard, the present study evaluates the effect of change in magnitude of loading on shallow foundations. For the study isolated foundation and raft foundation have been considered and analysed in Staad Pro. Four different magnitude of loading on the columns supported by the foundation have been considered in the study. Further, the foundations have been modeled in PLAXIS 2D software and the results have been compared with that obtained from STAAD Pro. in order to understand the influence of modeling soil as discrete springs (in STAAD Pro.) and continuum (in Plaxis 2D). From the study, it is observed that magnitude of loading has significant influence on behavior of foundation. The base pressure and settlement obtained from STAAD Pro. analysis is relatively uniform. However, the base pressure distribution obtained from PLAXIS 2D analysis varies significantly, although the settlement response is more uniform. The study demonstrates the soil-foundation interaction response of shallow foundations under different loading condition by using STAAD Pro. and Plaxis 2D analysis.

Objectives: Gold weight implantation in the upper eyelid is a frequently performed treatment for paralytic lagophthalmos to prevent corneal exposure. A margin reflex distance of -1 and -2 (MRD1, MRD2), the palpebral fissure height (PFH), and the vertical lagophthalmos (LV) are 1-dimensional (1D) measurements used in follow-up. Because the exposure area is 2-dimensional (2D), this study was designed to investigate the results using both 1D and 2D analysis. Methods: Ten patients who underwent pretarsal suborbicularis oculi gold weight implantation were included in the study. Photographs were taken with a digital camera and the images were analyzed using ImageJ software (US National Institutes of Health, Bethesda, MD, USA). The lagophthalmos area (LA) and ocular surface area (OSA) were measured in 2D in addition to the MRD1, MRD2, PFH, LV. Preoperative and postoperative values were compared using the Wilcoxon signed-rank test. Associations between parameters were evaluated using Spearman's correlation analysis. Results: The mean age of the patients (7 male, 3 female) was 39.6±16.4 years (range: 14–60 years). The mean implant weight was 1.46 g (0.8–1.6 g). There were significant reductions in the MRD1, MRD2, PFH, OSA, LV, and LA values after surgery (p

International audience; Ediacaran-Cambrian bioturbation on bedding planes provides physical and chemical data about the environmental conditions and biological activities of early metazoans. We propose a quantitative method to estimate horizontal disruption of the substrate using bedding-plane trace fossils from Brioverian deposits. This methodology provides the first quantitative analysis of the trace fossil assemblage from the Armorican Massif (Brittany, NW of France). The Ediacaran-Cambrian transition within the Brioverian series is characterized by the abundance of simple and horizontal trace fossils such as Helminthopsis, Helminthoidichnites, and Palaeophycus as well as rare Gordia and Spirodesmos. Recent U-Pb dating has been carried out on detrital zircon grains from the upper Brioverian series suggesting a late Ediacaran to Fortunian age of the fossiliferous deposits (ca. 550 to 530 Ma). With Arc-Gis software, we use a semi-quantitative approach to estimate the relative 2D bioturbation rate recorded on bedding planes. The dataset is used to discuss the feeding strategies and how the seafloor ecospace was colonized by the early bilaterian metazoans. This approach combines new values such as: the length of a trace fossil, the surface of a trace, the cumulative length, and the cumulative surfaces from all of the ichnofossils recorded on the same slate surface, to finally suggest that the bioturbation rate of the microbial grazers impacted the use of the seafloor ecospaces and feeding strategies through the biomats.; La bioturbation visible en surface de banc dans les dépôts édiacariens-cambriens fournit des informations physiques et chimiques concernant les conditions environnementales et les activités biologiques des premiers métazoaires. Nous proposons une méthode quantitative pour estimer la bioturbation horizontale du substrat à partir des traces fossiles préservées sur des plaques de schistes provenant des dépôts briovériens de Bretagne, dans le Massif Armoricain (N-O France). Le passage Ediacarien-Cambrien au sein de la série briovérienne est documenté par l’abondance de traces fossiles horizontales simples telles que les ichnogenres Helminthopsis, Helminthoidichnites et Palaeophycus et la présence, plus rare, de Gordia et Spirodesmos. De récentes datations U-Pb réalisées sur des zircons détritiques du Briovérien supérieur ont révélé un âge s’étalant entre l’Ediacarien tardif et le début du Fortunien pour ces dépôts fossilifères (ca. 550 à 530 Ma). Avec une approche semi-quantitative, menée avec le logiciel Arc-Gis, nous avons estimé la bioturbation 2D relative visible en surface des niveaux schisteux. Les données obtenues permettent de discuter les stratégies d’alimentation et la colonisation de l’éco-espace benthique par les premiers métazoaires bilatériens. Cette approche combine des nouvelles données : la longueur d’une trace fossile et sa surface, la longueur et la surface cumulées des traces présentes sur une même surface de banc (ou plaques de schistes), et donne finalement une idée relative de la densité en organismes présents sur le substrat, tout en suggérant que le taux de bioturbation a impacté la répartition des organismes brouteurs et les stratégies d’alimentation à travers les biomats.

Abstract Cilia are hair-like membrane protrusions that emanate from the surface of most vertebrate cells and are classified into motile and primary cilia. Motile cilia move fluid flow or propel cells, while also fulfill sensory functions. Primary cilia are immotile and act as a cellular antenna, translating environmental cues into cellular responses. Ciliary dysfunction leads to severe diseases, commonly termed ciliopathies. The molecular details underlying ciliopathies and ciliary function are, however, not well understood. Since cilia are small subcellular compartments, imaging-based approaches have been used to study them. However, tools to comprehensively analyze images are lacking. Automatic analysis approaches require commercial software and are limited to 2D analysis and only a few parameters. The widely used manual analysis approaches are time consuming, user-biased, and difficult to compare. Here, we present CiliaQ, a package of open-source, freely available, and easy-to-use ImageJ plugins. CiliaQ allows high-throughput analysis of 2D and 3D, static or time-lapse images from fluorescence microscopy of cilia in cell culture or tissues, and outputs a comprehensive list of parameters for ciliary morphology, length, bending, orientation, and fluorescence intensity, making it broadly applicable. We envision CiliaQ as a resource and platform for reproducible and comprehensive analysis of ciliary function in health and disease. Graphic abstract

Background Narrowing of the acromiohumeral distance (AHD) implies a rotator cuff tear. However, conventional AHD measurements using two-dimensional (2D) imaging or with the patient in the supine position might differ from that while standing during daily activity. This study aimed to evaluate the three-dimensional (3D) actual distance between the acromion and humeral head in the standing position and compare the AHD values with those obtained using conventional measuring methods. Methods Computed tomography (CT) images of 166 shoulders from 83 healthy volunteers (31 male and 52 female; mean age 40.1 ± 5.8 years; age range, 30–49 years) were prospectively acquired in the supine and standing positions using conventional and upright CT scanners, respectively. The minimum distance between the acromion and humeral head on the 3D surface models was considered as the 3D AHD. We measured the 2D AHD on anteroposterior digitally reconstructed radiographs. The AHD values were compared between the supine and standing positions and between the 2D and 3D measurements. Results The mean values of 2D AHD were 8.8 ± 1.3 mm (range, 5.9–15.4 mm) in the standing position and 8.1 ± 1.2 mm (range, 5.3–14.3 mm) in the supine position. The mean values of 3D AHD were 7.3 ± 1.4 mm (range, 4.7–14.0 mm) in the standing position and 6.6 ± 1.2 mm (range, 4.4–13.7 mm) in the supine position. The values of 3D AHD were significantly lower than those of 2D AHDs in both the standing and supine positions (P < 0.001). The values of 2D and 3D AHDs were significantly lower in the supine position than in the standing position (P < 0.001). Conclusions This study evaluated the 3D AHD of normal shoulders in the standing position using an upright CT scanner. The present results indicated that assessments in the supine position can underestimate the value of the AHD compared with those made in the standing position and that assessments using 2D analysis can overestimate the value.

Landslide is a sudden slide of rock, debris and earth down the slope. The Nilgiris have always been under the threat of landslides in monsoon season. The Nilgiris is a hilly district with an area of 2500 km2 located in the North-Western part of Tamil Nadu. Rainfall is the major triggering factor of landslides in The Nilgiris (Chandrasekaran in Assessment of damages induced by recent landslides in Ooty, Tamil Nadu, India. IIT Bombay, Mumbai, India, pp 687–688, 2010). In this study, two sites have been selected where landslides occurred during monsoon in November 2009. The soil samples were collected from the sites of landslides. A detailed investigation was carried out on the soil samples and index properties; chemical composition and shear strength parameters were drawn. The critical surface for the slope was drawn graphically using Fellenius (1936) method, and the same was incorporated into the software through co-ordinates. Many studies have been carried out using numerical analysis for The Nilgiris area but in this study, realistic site conditions and parameters have been incorporated. The analysis was carried using wetting depths of 2 m, 3 m, 4 m and 5 m at the edge of the slopes and shear strength parameters in GEO 5 and PLAXIS 2D software. The analysis result shows that the infiltration of water into the slope results in the reduction of shear strength parameter of the soil which leads to the failure of the slope. The results of Geo 5 analysis and PLAXIS 2D analysis were compared, and the conclusions were drawn from it.

Numerically modeled vortex chamber, both in 2D and 3D, have been employed to analyze the flow features of tornado-like vortex. In 2D analysis, flow structure was first investigated using a fixed overall height and varying swirl ratios (S) followed by the variation of overall chamber height to observe its effect on touchdown S. Increasing overall chamber height lowered the touchdown S. Ground pressure profile showed some contrast from experiment as the pressure was found to be increasing even after touchdown. A tentative projection of overall chamber height required to obtain touchdown similar to experiment was found to be at H = 49.5. The proposition of increasing the chamber height alone to reach touchdown state would make the analysis computationally intensive and potentially infeasible. For further analysis, 3D model, brought in action, revealed touchdown to occur at similar parameters with similar trend of pressure plot as the 2D model.

We sought to determine whether a measure combining changes in C-peptide and glucose could show efficacy 3 months after teplizumab treatment among multiple islet autoantibody+ dysglycemic individuals (n=44, age 19.2± 11.9 yrs on teplizumab and n=32, age 17.5± 11.1 yrs on placebo) in the recent TrialNet teplizumab prevention trial (teplizumab delayed T1D onset). In the 2D analysis assessing changes in glucose and C-peptide below (Figure), mean glucose and C-peptide from 30 to 120 minutes are plotted from baseline and 3-month OGTTs. For each OGTT, centroids (central point of OGTT shape) are connected by vectors, showing opposite directionality from baseline to 3 months between groups. Since AUC C-peptide/AUC glucose (AUC Ratio) correlates highly with centroid C-peptide/centroid glucose (r=0.99), to quantify the differences in directionality, we compared AUC Ratio (x1,000; adjusted for baseline) change from baseline to 3 months. The teplizumab group showed a positive change in AUC Ratio: 1.5±2.9 vs. a negative change in placebo: - 0.78±2.7; p=0.001). This difference was sustained after 6 months of treatment (p=0.004). In summary, a 2D analysis of glucose and C-peptide change provided visual and quantitative evidence of an early treatment effect. As a centroid correlate, the AUC Ratio can be a useful endpoint for performing shorter prevention trials. Disclosure E.K. Sims: None. M.V. Warnock: None. K.C. Herold: Consultant; Self; Provention Bio, Inc. J. Sosenko: None. Funding National Institutes of Health; National Institute of Diabetes and Digestive and Kidney Diseases; National Institute of Allergy and Infectious Diseases; Eunice Kennedy Shriver National Institute of Child Health and Human Development; JDRF

Sholl analysis is used to quantify the dendritic complexity of neurons. Differences between two-dimensional (2D) and three-dimensional (3D) Sholl analysis can exist in neurons with extensive axial stratification of dendrites, however, in retinal ganglion cells (RGCs), only 2D analysis is typically reported despite varying degrees of stratification within the retinal inner plexiform layer. We determined the impact of this stratification by comparing 2D and 3D analysis of the same RGCs.Twelve retinas of mice expressing yellow fluorescent protein in RGCs under the control of the Thy1 promotor were whole-mounted. The entire dendritic arbor of 120 RGCs was traced, after which 2D and 3D Sholl analysis was performed. Two parameters describing dendritic complexity; area under the curve (AUC) and peak number of intersections (PNI) were then derived and analyzed.The AUC and PNI were significantly higher with 3D analysis compared to 2D analysis with medians of 2805 and 2508 units, and 31 and 27, respectively (P 0.01). Both 2D and 3D AUC increased with arbor thickness. The discrepancy in AUC between the two methods depended on mean AUC (with every 1 unit increase in mean AUC resulting in a discrepancy of 0.1 unit), but not arbor thickness.In RGCs imaged in vitro, there is a difference in AUC and PNI derived with 2D and 3D Sholl analysis. Where possible, 3D Sholl analysis of RGCs should be performed for more accurate quantitative analysis of dendritic structure.

Selective laser sintering (SLS) is an important additive manufacturing method for polymers and is increasingly used for industrial applications. To improve the quality of printed products a thorough understanding of the process is necessary. Simulations are a convenient way to assess the sintering in detail. In literature several numerical studies can be found on the sintering process of two particles. Both 2D and 3D geometries are used and sometimes the assumption of axisymmetry is made. If the effect of the laser beam in temperature-dependent sintering is taken into account, axisymmetry cannot be assumed anymore and full 3D simulations are required. However, these simulations are complex and computationally expensive. In this work, we assess if 2D simulations are representative for the 3D case of the temperature-dependent sintering process of two viscous particles. We find that 2D simulations are a good alternative for 3D simulations for the sintering problem of two particles, if the correct geometrical scaling factors are taken into account.

The purpose of the present study was to determine the impact of image quality on the results of air void system parameters determination in air-entrained concretes. The focus was on technical aspects related to the preparation of the scanned image of the concrete surface, which was then subjected to 2D surface analysis. Image processing aimed at separating joined voids and removing various types of defects in aggregate and cement mortar. The specific surface of the voids was determined with the air void equivalent diameter or perimeter as the calculation basis. Applying the Schwartz&ndash, Saltykov method, the 3D distribution of the air voids was reconstructed based on 2D measurements. On this basis, the micro-air content A300 was determined. The results of the 2D method were compared with the results of determinations carried out using the linear traverse (1D) method according to EN 480-11. The tests confirm the need to correct the image prior to measurements. Comparative tests showed good agreement between the air void system parameters determined using the 2D analysis and the EN 480-11 chord length counting method.

Background To investigate and compare the gap (i.e. fit) and thickness of six aligner systems (Airnivol, ALL IN, Arc Angel, F22, Invisalign and Nuvola) using industrial computed tomography (CT). The null hypothesis was that there would be no detectable differences in either measurement between the aligners investigated. Materials and methods Passive aligners of each brand were fitted to one single resin cast prototyped from an STL file from a single patient. The samples obtained were examined under high-resolution micro-CT, and the resulting tomographic microphotographs and volumetric data were compared. 3D analysis investigated the gap volume, the mean gap width and the maximum gap width of each sample. A total of 204 linear 2D measurements were made on 18 microtomographic images to investigate the aligner gap and thickness among different systems. Investigated regions were the central incisor, canine and first molar. The resulting measurements were analysed by ANOVA and compared using Tukey’s post hoc analysis (P < 0.05). Results 3D analysis revealed that the F22 displayed lower gap volume and mean gap width, followed by Airnivol and Invisalign, whereas Airnivol the lowest maximum gap width. 2D analysis showed that F22 had the lowest mean gap and aligner thickness at all teeth investigated. Comparison of the 2D point values revealed statistically significant differences between brands in terms of both measurements (P < 0.05), with the exception of six points in the gap analysis and one in the thickness analysis. Conclusions There are differences between the six aligner systems examined in terms of 2D and 3D measurements of aligner thickness and gap.

In 2014, a cutting slope was excavated in Guizhou Province in China during the construction of the YanDe highway when a previously unknown ancient landslide was encountered. It has subsequently been named the ‘Longjiayan ancient landslide’. Large surface cracks and severe building damage occurred, as well as apparent ground subsidence. This work reports the results of a comprehensive investigation performed to identify the mechanism and process of reactivation of the ancient landside. In situ surveys and mapping activities were first carried out to obtain a preliminary delineation of the landslide surface, and 19 boreholes were set up in the reactivation area to determine the landslide structure, as well as create a picture of the sliding surfaces involved. Then, 41 surface cracks and deep displacements in eleven boreholes were monitored for over 40 days. A numerical 2D analysis was also undertaken to back analyze the landside. A conceptual model is proposed for interpreting the mechanisms responsible for reactivation of ancient landslides based on the Longjiayan landslide. Thereafter, based on the formation mechanism of the landslide, detailed reinforcement measures were proposed to control it. The results reveal that the landslide was a retrogressive soil-mass slide involving two sliding surfaces. These surfaces have different depths: one is shallow and located in a silty clay layer; the other is deep and lies in a completely weathered shale layer. The soil mass primarily slid towards the free surface along the deep sliding surface. Up to three failure stages have been identified in the landslide which was triggered by excavation in the toe region. Rainfall and adverse dip direction of weak intercalations further promoted the development of the landslide. During this process, the shallow landslide played a key role in the formation of the deep landslide. Appropriate use of anti-slide piles and water interception/drainage is an effective approach to controlling such landslides.

Earthquakes pose critical danger for seismically deficient structures. This phenomenon becomes more pronounced in underdeveloped countries where such structures are common. 2D analysis of such stru...

This study proposes a method for predicting the impregnation time in the thickness direction of vacuum-assisted resin transfer molding (VaRTM) with flow media using 2D impregnation analysis and machine learning to reduce the computation time. We first let the machine learn the relationship between the impregnation time and the state of the flow media using a VaRTM 3D analysis. To predict the impregnation time in the thickness direction with low computation cost, a 2D analysis of the flow media portion was performed, and the impregnation time was predicted based on the 2D results and pre-trained machine learning program. For the prediction of a flat plate model with injection points that were different from the training model, the impregnation time error was 6.31%. Further, when using the machine learning model for the flat plate model, the analysis time was reduced to approximately 0.74% of the time required for the 3D analysis.