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Compact wearable mapping system (WMS) has gained significant attention due to their convenience in various applications. Specifically, it provides an efficient way to collect prior maps for 3D structure inspection and robot-based "last-mile delivery" in complex environments. However, vibrations in human motion and the uneven distribution of point cloud features in complex environments often lead to rapid drift, which is a prevalent issue when applying existing LiDAR Inertial Odometry (LIO) methods on low-cost WMS. To address these limitations, we propose a novel LIO for WMSs based on Hybrid Continuous Time Optimization (HCTO) considering the optimality of Lidar correspondences. First, HCTO recognizes patterns in human motion (high-frequency part, low-frequency part, and constant velocity part) by analyzing raw IMU measurements. Second, HCTO constructs hybrid IMU factors according to different motion states, which enables robust and accurate estimation against vibration-induced noise in the IMU measurements. Third, the best point correspondences are selected using optimal design to achieve real-time performance and better odometry accuracy. We conduct experiments on head-mounted WMS datasets to evaluate the performance of our system, demonstrating significant advantages over state-of-the-art methods. Video recordings of experiments can be found on the project page of HCTO: https://github.com/kafeiyin00/HCTO. [ABSTRACT FROM AUTHOR]

Objective: The talus is an important component in the ankle, and its treatment after injury is crucial. However, complications and adverse events due to incomplete traditional classifications may still occur, and these classifications fail to analyze the patterns and distribution of fractures from a three‐dimensional perspective. Therefore, in this study, we aimed to analyze the location and distribution of fracture lines in different types of talus fractures using three‐dimensional (3D) and heat mapping techniques. Additionally, we aimed to determine the surface area of the talus that can be utilized for different approaches of internal fixation, aiding in the planning of surgical procedures. Methods: We retrospectively analyzed data from CT scans from 126 patients diagnosed with talus fractures at our two hospitals. We extracted the CT data of a healthy adult and created a standard talus model. We performed 3D reconstruction using patients' CT images and superimposed the fracture model onto the standard model for drawing fracture lines. Subsequently, we converted the fracture lines into a heat map for visualization. Additionally, we measured 20 specimens to determine the boundary for various ligaments attached to the talus. We determined the surface area of the talus available for different surgical approaches by integrating the boundary data with previously reported data on area of exposure. Results: Without considering the displacement distance of the fracture, fracture types were classified as follows, by combining Hawkins and Sneppen classifications: talar neck, 41.3%; posterior talar tubercle, 22.2%; body for the talus and comminuted, 17.5%; lateral talar tubercle, 11.9%; and talar head, 7.1%. We established fracture line and heat maps using this classification. Additionally, we demonstrated the available area for anteromedial, anterolateral, posteromedial, posterolateral, and medial malleolus osteotomy and Chaput osteotomy approaches. Conclusion: Fracture line and heat map analyses can aid surgeons in planning a single or combined surgical approach for the reduction and internal fixation of talus fractures. Demonstrating the different surgical approaches can help surgeons choose the most effective technique for individual cases. [ABSTRACT FROM AUTHOR]

This paper introduces an innovative approach to 3D environmental mapping through the integration of a compact, handheld sensor package with a two-stage sensor fusion pipeline. The sensor package, incorporating LiDAR, IMU, RGB, and thermal cameras, enables comprehensive and robust 3D mapping of various environments. By leveraging Simultaneous Localization and Mapping (SLAM) and thermal imaging, our solution offers good performance in conditions where global positioning is unavailable and in visually degraded environments. The sensor package runs a real-time LiDAR-Inertial SLAM algorithm, generating a dense point cloud map that accurately reconstructs the geometric features of the environment. Following the acquisition of that point cloud, we post-process these data by fusing them with images from the RGB and thermal cameras and produce a detailed, color-enriched 3D map that is useful and adaptable to different mission requirements. We demonstrated our system in a variety of scenarios, from indoor to outdoor conditions, and the results showcased the effectiveness and applicability of our sensor package and fusion pipeline. This system can be applied in a wide range of applications, ranging from autonomous navigation to smart agriculture, and has the potential to make a substantial benefit across diverse fields. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Focal atrial tachycardia (FAT) is an organized atrial rhythm >100 beats per minute initiated from a discrete origin and spreading over both atria in a centrifugal pattern. The arrhythmia may be sustained or incessant. Dynamic forms with recurrent interruptions and reinitiating may be frequent. In this report, we present a 36‐year‐old man who came to the emergency room complaining of palpitation and shortness of breath. All laboratory evaluations were normal. With an initial electrocardiogram (ECG) the patient was admitted with the initial diagnosis of atrial flutter. Finally, after the electrophysiologist's examination, with the diagnosis of FAT, ablation was successfully performed. Atrial tachycardia (AT), excluding atrial fibrillation (AF) and cavotricuspid isthmus‐dependent atrial flutter (AFL), account for 10% of supraventricular tachycardia referred for ablation procedures. More than 70% of these cases are focal and occur in patients with no records of cardiac surgery or ablation of AF. FAT originating from the right pulmonary veins (PV) can be challenging to differentiate from atrial flutter due to their proximity and overlapping symptoms. The right PV is close to the right atrium, and the abnormal electrical activity in FAT may mimic the organized circuit found in atrial flutter. Distinguishing between FAT and atrial flutter is crucial for choosing the best therapeutic option. This can be done most of the time by focusing on the differences in the pattern of their P and QRS waves, R‐R wave intervals, and also their baseline changes on ECG, as well as their cycle duration, response to adenosine and risk factors of the patient. [ABSTRACT FROM AUTHOR]

Traversing through challenging, unstructured environments, particularly in mining scenarios characterized by dust concentration, darkness, and lack of communication presents formidable obstacles for traditional sensing technologies. Drawing inspiration from naked mole rats, characterized as being skilled subterranean navigators that depend heavily on touch to navigate their environment, this study introduces a new whisker-sensing disk designed for 3D mapping in unstructured environments. The disk comprises a circular array of 32 whisker sensors, each featuring a slender flexible plastic rod attached to a compliant base housing a 3D Hall-effect sensor. The whisker sensor is modeled using both analytical and data-driven approaches to predict rotation angles based on magnetic field measurements. The validation and comparison of both models are performed by evaluating data from other whisker sensors. Additionally, a series of experiments demonstrates the whisker disk's capability in performing 3D-mapping tasks, along with successful implementation on diverse robotic platforms, highlighting its future potential for effective 3D mapping in complex and unstructured subterranean environments. [ABSTRACT FROM AUTHOR]

Introduction: It would be helpful in determining ablation strategy if the occurrence of perimitral atrial tachycardia (PMAT) could be predicted in advance. We investigated whether estimated perimitral conduction time (E‐PMCT), namely, twice the time between coronary sinus (CS) pacing and the ensuing wave‐front collision at the opposite side of the mitral annulus, correlated with the cycle length of PMAT and could predict future PMAT. Methods and Results: We retrospectively (retrospective cohort) and prospectively (validation cohort) investigated atrial fibrillation patients who had received pulmonary vein isolation (PVI) and in whom left atrial maps had been created during CS pacing. We calculated their E‐PMCT. PMAT was observed either by provocation or during follow‐up in 25, AT other than PMAT was observed in 24 (non‐PMAT AT group), and 53 patients never displayed any AT (no‐AT group) in the retrospective cohort. In the PMAT group of the retrospective cohort, a strong positive correlation was observed between the PMAT CL and E‐PMCT (r =.85, p < 0.001). PMAT was never induced nor observed in patients with E‐PMCT less than 176 ms, and the best cut‐off value for PMAT was 180 ms by receiver‐operating characteristic curve analysis. In the validation cohort of 76 patients, the cut‐off value of the E‐PMAT less than 180 ms predicted noninducibility of PMAT, with a sensitivity of 78.6%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 25.0%. Conclusion: Short E‐PMCT may predict noninducibility of PMAT and guide a less invasive ablation strategy. [ABSTRACT FROM AUTHOR]

Pulmonary vein isolation (PVI), as the cornerstone of atrial fibrillation (AF) ablation, has emerged a widely used therapy for patients suffering from AF. To improve PVI efficiency, single-shot catheters (SSCs) have been developed. Regrettably, SSCs are not integrated into 3D-mapping technology. In that regard, a novel radiofrequency balloon catheter (RFBC, Heliostar, Biosense Webster) with full integration into 3D-mapping technology has been developed. The aim of this study was to assess operative and follow-up outcomes of the RFBC in AF patients. In this monocentric prospective registry, patients with a first-time PVI using the RFBC were included. Follow-up visits were scheduled 3, 6, 12 and 24 months after ablation and in case of symptoms. A total of 171 patients (36.8% female) were included, with a mean age of 68.5 ± 10.2 years. Among them, 63 patients (36.8%) presented with persistent AF. Notably, no major periprocedural complications were observed. The mean follow-up period was 287 ± 157 days. In the Kaplan–Meier analysis, the estimated recurrence-free survival after 12 months was 81.8%. Based on our data, PVI with the fully 3D-mapping-integrated RFBC seems to be safe and effective and to have a favorable 12-month outcome in patients with paroxysmal and persistent AF. [ABSTRACT FROM AUTHOR]

Purpose: One of the major limitations of the 2D fracture evaluation (Schatzker classification) is its failure to adequately assess fracture lines in the frontal plane and fracture displacement in the antero-posterior direction. 3D fracture line mapping includes steric assessment which can aid decision making with regards to the surgical approach and fixation scheme. We hypothesized that there are consistent fracture patterns and zones of comminution for proximal tibial fractures. Methods: Radiographic data of 228 proximal tibia fractures were retrospectively included in this study. Fracture lines and zones of comminution were graphically superimposed onto a 3D template of an intact tibia after virtual reduction and normalization to identify major patterns of fracture and comminution. Results: Out of 206 male and 21 female patients, 89 had a fracture of the lateral condyle only (Schatzker I and II), 53 involved the medial plateau only (Schatzker IV) and 86 had a high-grade fracture involving both the condyles (Schatzker V and VI). 64.5% of the fracture lines involving the medial plateau alone were in the coronal plane, and this number was even lesser (44.2%) in medial plateau involvement of bicondylar fractures. In bicondylar fractures, lines were usually not seen to pass directly through the posteromedial region. Conclusions: Medial tibial plateau fractures have a mix of coronal or sagittal fracture alignment. A clearer understanding of the 3D orientations of fractures based on CT scans can aid in diagnosing the pattern of fracture and adequate positioning of plates can be done to eventually improve operative outcomes. [ABSTRACT FROM AUTHOR]

High-resolution topographic mapping is essential for scientific investigations and operational exploration of planets, such as Mars. Photoclinometry, which uses light scattered from a surface to reconstruct 3D topography, can retrieve subtle topographic details from monocular images. However, its performance is affected by the atmosphere of Mars, which alters surface reflectance mechanisms due to the scattering and absorption by aerosols. Therefore, specific treatments accounting for these atmospheric effects are needed to enable photoclinometric mapping of Mars. This paper presents a novel photoclinometric approach incorporating a radiative-transfer model of atmospheric scattering effects for pixel-wise 3D reconstruction of the Martian surface. The approach requires a high-resolution image, a corresponding coarse-resolution digital elevation model (DEM), and information of the optical depth as inputs. A radiative transfer model adapted to the Martian atmosphere is used to account for the atmospheric effects. The approach also allows directly adopting optical depth estimates from a global database (e.g., the Mars Climate Database). The approach was validated using different types of Mars orbiter images collected by cameras on-board the Mars Reconnaissance Orbiter and the Tianwen-1 Orbiter. The results indicate that the approach can achieve a geometric accuracy (in terms of root-mean-squared error (RMSE) of the elevation) of approximately 2 pixels of the image resolution and significantly enhances topographic details. In addition, we evaluated the approach using different settings for the optical depths and spatial resolutions of the input DEMs. The results show that overestimating the optical depth leads to overestimation of topographic amplitudes (e.g., deeper craters). On the other hand, underestimating the optical depth by the same amount as overestimation leads to a smaller increase in the RMSE. Moreover, coarsening the resolution of an input DEM increases the RMSE of the photoclinometric results. Nevertheless, photoclinometry improves both the RMSE and the resolution of the input DEM. This new approach serves as an effective means for applying photoclinometry for pixel-wise 3D topographic mapping of the Martian surface. This will facilitate exploitation of the large number of high-resolution monocular images of Mars in 3D topographic mapping of the planet. [ABSTRACT FROM AUTHOR]

Progress toward habitat protection goals can effectively be performed using satellite imagery and machine-learning (ML) models at various spatial and temporal scales. In this regard, habitat types and landscape structures can be discriminated against using remote-sensing (RS) datasets. However, most existing research in three-dimensional (3D) habitat mapping primarily relies on same/cross-sensor features like features derived from multibeam Light Detection And Ranging (LiDAR), hydrographic LiDAR, and aerial images, often overlooking the potential benefits of considering multi-sensor data integration. To address this gap, this study introduced a novel approach to creating 3D habitat maps by using high-resolution multispectral images and a LiDAR-derived Digital Surface Model (DSM) coupled with an object-based Random Forest (RF) algorithm. LiDAR-derived products were also used to improve the accuracy of the habitat classification, especially for the habitat classes with similar spectral characteristics but different heights. Two study areas in the United Kingdom (UK) were chosen to explore the accuracy of the developed models. The overall accuracies for the two mentioned study areas were high (91% and 82%), which is indicative of the high potential of the developed RS method for 3D habitat mapping. Overall, it was observed that a combination of high-resolution multispectral imagery and LiDAR data could help the separation of different habitat types and provide reliable 3D information. [ABSTRACT FROM AUTHOR]

Background: A 70‐year‐old man revealed a rare type of atrioventricular nodal re‐entrant tachycardia (AVNRT) involving distinct retrograde pathways, superior slow pathway, and inferolateral left atrial slow pathway. Result: Radiofrequency ablation was successfully performed on the noncoronary cusp and in the left atrium, respectively, to eliminate the tachycardias. Discussion and Conclusion: Due to the anomalous electrical conduction patterns, careful diagnosis and ablation strategies were necessary to avoid the risk of atrioventricular block. These findings underscore the diversity and complexity of AVNRT and highlight the importance of tailored therapeutic approaches. [ABSTRACT FROM AUTHOR]

The marine self-potential (SP) method is currently playing an increasing role in the exploration and resource evaluation of seafloor massive sulfide (SMS) deposits. SP surveys are conducted using autonomous underwater vehicles (AUV), which yield multicomponent electric field datasets. By comparing with the single-component electrical field data used to date, the inversion of these multicomponent data is expected to provide a more accurate description of the 3D structure of SMS deposits beneath the seafloor (like gradiometry in gravity surveys). We introduce an inversion algorithm specifically adapted to multicomponent SP data. A synthetic model demonstrates that the inversion of multicomponent datasets allows us to better recover the amplitude of the current density and the morphology of the ore bodies compared to using a single component of the electrical field. Next, we apply our approach to a multicomponent SP dataset collected during the DY58 oceanic cruise at the Yuhuang hydrothermal field on the Southwest Indian Ridge. Subsequently, we reconstruct the three-dimensional (3D) geometry of the SMS deposits beneath the seafloor. The AUV-based SP system with the collection of multicomponent SP data inversion appears to be a powerful tool in the exploration and evaluation of seafloor sulfide resource and, in the future, could be used in concert with induced polarization data. [ABSTRACT FROM AUTHOR]

Photorealistic 3D models are important data sources for digital twin cities and smart city applications. These models are usually generated from data collected by aerial or ground-based platforms (e.g., mobile mapping systems (MMSs) and backpack systems) separately. Aerial and ground-based platforms capture data from overhead and ground surfaces, respectively, offering complementary information for better 3D mapping in urban areas. Particularly, backpack mapping systems have gained popularity for 3D mapping in urban areas in recent years, as they offer more flexibility to reach regions (e.g., narrow alleys and pedestrian routes) inaccessible by vehicle-based MMSs. However, integration of aerial and ground data for 3D mapping suffers from difficulties such as tie-point matching among images from different platforms with large differences in perspective, coverage, and scale. Optimal fusion of the results from different platforms is also challenging. Therefore, this paper presents a novel method for the fusion of aerial, MMS, and backpack images and point clouds for optimized 3D mapping in urban areas. A geometric-aware model for feature matching is developed based on the SuperGlue algorithm to obtain sufficient tie-points between aerial and ground images, which facilitates the integrated bundle adjustment of images to reduce their geometric inconsistencies and the subsequent dense image matching to generate 3D point clouds from different image sources. After that, a graph-based method considering both geometric and texture traits is developed for the optimal fusion of point clouds from different sources to generate 3D mesh models of better quality. Experiments conducted on a challenging dataset in Hong Kong demonstrated that the geometric-aware model could obtain sufficient accurately matched tie-points among the aerial, MMS, and backpack images, which enabled the integrated bundle adjustment of the three image datasets to generate properly aligned point clouds. Compared with the results obtained from state-of-the-art commercial software, the 3D mesh models generated from the proposed point cloud fusion method exhibited better quality in terms of completeness, consistency, and level of detail. [ABSTRACT FROM AUTHOR]

Aim: The implementation of 3D mapping systems plays an important role in interventional electrophysiology (EP) in recent years. The aim of the present study was to evaluate use of 3D mapping systems regarding fluoroscopy and procedure duration. Method: In the "Go for Zero Fluoroscopy" project 25 European centers provided data of consecutive EP procedures. Data on use of 3D mapping systems as well as utilization of contact force catheters and multipolar mapping catheters were associated with fluoroscopy time, dose area product (DAP), and procedure duration. Result: A 3D mapping system was used in 966 (54%) cases. Use of 3D mapping for atrioventricular nodal reentry tachycardia (AVNRT) was associated with reduced fluoroscopy time (p < 0.001), DAP (p = 0.04) but increased procedure time (p = 0.029). Moreover, fluoroscopy time (p < 0.001) and DAP (p = 0.005) were significantly lower in the 3D mapping group in ablation of typical atrial flutter. However, the procedure time (p < 0.001) increased. Use of 3D mapping in the ablation of accessory pathway (AP) was associated with reduced fluoroscopy time (p < 0.001) and DAP (p < 0.001) with no significant increase in procedure time (p = 0.066). In the case of atrial fibrillation, a 3D mapping system was used in 485 patients (75.8%). Additional use of a contact force catheter was associated with lower fluoroscopy time (p < 0.001) and DAP (p < 0.001). Use of a multipolar mapping catheter was associated with lower fluoroscopy time (p = 0.002). The implementation of 3D mapping systems in the ablation of ventricular tachycardias resulted in a significant increase in the procedure time (p = 0.001) without significant differences regarding the DAP (p = 0.773) and fluoroscopy time (p = 0.249). Conclusion: Use of 3D mapping systems in ablation of supraventricular tachycardias is associated with lower radiation exposure. Nevertheless, the procedure time often increases, except in the case of ablation for AP. Use of contact force catheters and multipolar mapping catheters is associated with yet lower radiation exposure values. Prospective randomized studies are needed to further elucidate potential benefit of these technological tools. [ABSTRACT FROM AUTHOR]

The architectural heritage of the 20th century is affected by several conservation problems in terms of material preservation, structural analysis, and reuse. Among these, material degradation and durability issues are the ones that have the most effect on the health state and, consequently, the survival of the constructions of the period. In order to conduct a proper analysis for preservation purposes, an interdisciplinary approach is necessary. The parabolic arch in Morano sul Po (Italy) is a reinforced concrete landmark in the Casale Monferrato area and is related to the industrial vocation of the territory, which is indissolubly linked to the cement production chain. The present paper reports the results of a non-destructive test campaign by a Politecnico di Torino multidisciplinary group, which combined acquisitions using different methods. The paper highlights the importance of a structured procedure to integrate different information coming from different techniques. The aim was to assess the health state of the structure and define the best procedures for building an information system based on the as-built modeling strategy, which could serve as the basis to provide conservation guidelines. [ABSTRACT FROM AUTHOR]

Purpose: To characterize the fracture patterns of acetabular fractures and create fracture maps and comminution zones based on three-dimensional (3D) computed tomography (CT) images. Methods: Sixty-eight computed tomography images of 67 patients (47 male [70.1%] and 20 female [29.9%], mean age: 45.2 ± 17.2 [range, 18–85 years] with the diagnosis of intra-articular acetabulum fracture were analyzed. Individual fracture lines were drawn and superimposed to a healthy acetabular template according to Judet-Letournel and simplified fracture classification systems. Fracture line, comminution zone, and heat maps were created using the computed tomography mapping technique. Results: Fracture lines were distributed mainly in a horizontal and oblique orientation, which concentrated in the anteroinferior part of the joint in anterior fractures. Posterior fractures mostly had an oblique orientation, which lied between the acetabular dome and middle part of the posterior wall. In complex fractures, fracture lines were concentrated just above the cotyloid fossa, acetabular dome, and posterosuperior part of the acetabulum. The most common comminuted zones were around the central area of the articular surface and the anterior wall in anterior fractures, between the cotyloid fossa and dome in complex fractures, and the upper half posterior wall. Conclusion: Fracture patterns and comminution zones of acetabular fractures displayed certain characteristics. Some areas had higher comminution zones, and some areas remained intact in repeatable fracture patterns. These results may help surgeons in fixing acetabular fractures, designing new implants, and placement of acetabular component while performing THA after acetabular fractures. [ABSTRACT FROM AUTHOR]

We assess the accuracy of Structure-from-Motion/Multiview stereo (SM) terrain models acquired ad hoc or without high-resolution ground control to analyze their usage as a base for inexpensive 3D bedrock geologic mapping. Our focus is on techniques that can be utilized in field projects without the use of heavy and/or expensive equipment or the placement of ground control in logistically challenging sites (e.g., steep cliff faces or remote settings). We use a Terrestrial Light Detection and Ranging (LiDAR) survey as a basis for the comparison of two types of SM models: (1) models developed from images acquired in a chartered airplane flight with ground control referenced by natural objects located on Google Earth scenes; and (2) drone flights with a georeference established solely from camera positions located by conventional, differentially corrected Global Navigation Satellite systems (GNSS). We find that all our SM models are indistinguishable in scale from the LiDAR reference model. The SM models do, however, show rigid body translations and rotations, with translations generally within the 1–5 m size of the natural objects used for ground control, the resolution of the GNSS receivers, or both. The rigid body rotations can be attributed to a poor imaging plan, which can be avoided with survey planning. Analyses of point densities in various models show a limitation of Terrestrial LiDAR point clouds as a mapping base due to the rapid falloff of resolution with distance. In contrast, SM models are characterized by relatively uniform point densities controlled by camera optics, the numbers of images, and the distance from the target. This uniform density is the product of the Multiview stereo step in SM processing that fills areas between key points and is important for bedrock geologic mapping because it affords direct interpretation on a point cloud at a relatively uniform scale throughout a model. Our results indicate that these simple methods allow SM model construction to be accurate to the range of conventional GNSS with resolutions to the submeter, even cm, scale depending on data acquisition parameters. Thus, SM models can, and should, serve as a base for high-resolution geologic mapping, particularly in a steep terrain where conventional techniques fail. Our SM models appear to provide accurate visualizations of geologic features over km scales that allow detailed geologic mapping in 3D with a relative accuracy to the decimeter or centimeter level and absolute positioning in the 2–5 m precision of GNSS; a geometric precision that will allow unprecedented new studies of any geologic system where geometry is the fundamental data. [ABSTRACT FROM AUTHOR]

The author discusses a study which examined the anatomical and conduction properties of regions of late ventricular myocardial activation during intrinsic rhythm and their correspondence with induced ventricular tachycardia (VT) circuits in 36 patients using the Intellamap Orion high-resolution mapping catheter and Rhythmia Hdx mapping system. Topics include description of the scar patterns and reason that voltage mapping has fallen out of favor in parts of the electrophysiology community.

The recently published "electrophysiologically guided low‐voltage bridge (LVB) strategy" is effective in the ablation of atrioventricular nodal re‐entry tachycardia (AVNRT) in children. This study aimed to evaluate its efficacy and safety in children <26 kgs. Fourteen children [64% males, median age 6.5 years (IQR 6–8 years), median weight 25.5 kg (IQR 24–26 kg)] with AVNRT were treated. In all patients, we detected a LVB associated to a typical slow pathway potential. The acute success rate was 100% with a mean of 5.5 cryoablation deliveries. All procedures were performed with near‐zero fluoroscopic exposure (median time 0.15 min, IQR 0–0.7 min), in six patients fluoroscopy was 0 min. There were no complications or recurrences during the follow‐up (median 20.91 months, IQR 11.7–26.7 months). [ABSTRACT FROM AUTHOR]

We demonstrate the creation of a large area of high-resolution (260 × 209 km2 at 1 m/pixel) DTM mosaic from the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images over the Chang'E-4 landing site at Von Kármán crater using an in-house deep learning-based 3D modelling system developed at University College London, called MADNet, trained with lunar orthorectified images and digital terrain models (DTMs). The resultant 1 m DTM mosaic is co-aligned with the Chang'E-2 (CE-2) and the Lunar Orbiter Laser Altimeter (LOLA)—SELenological and Engineering Explorer (SELENE) blended DTM product (SLDEM), providing high spatial and vertical congruence. In this paper, technical details are briefly discussed, along with visual and quantitative assessments of the resultant DTM mosaic product. The LROC NAC MADNet DTM mosaic was compared with three independent DTM datasets, and the mean differences and standard deviations are as follows: PDS photogrammetric DTM at 5 m grid-spacing had a mean difference of −0.019 ± 1.09 m, CE-2 DTM at 20 m had a mean difference of −0.048 ± 1.791 m, and SLDEM at 69 m had a mean difference of 0.577 ± 94.940 m. The resultant LROC NAC MADNet DTM mosaic, alongside a blended LROC NAC and CE-2 MADNet DTM mosaic and a separate LROC NAC, orthorectified image mosaic, are made publicly available via the ESA planetary science archive's guest storage facility. [ABSTRACT FROM AUTHOR]

In Bragg coherent diffractive imaging, the precise location of the measured crystals in the interior of the sample is usually missing. Obtaining this information would help the study of the spatially dependent behavior of particles in the bulk of inhomogeneous samples, such as extra-thick battery cathodes. This work presents an approach to determine the 3D position of particles by precisely aligning them at the instrument axis of rotation. In the test experiment reported here, with a 60 μm-thick LiNi0.5Mn1.5O4 battery cathode, the particles were located with a precision of 20 μm in the out-of-plane direction, and the in-plane coordinates were determined with a precision of 1 μm. [ABSTRACT FROM AUTHOR]

This paper describes an affordable robotic mobile 3D mapping system. It is built with Livox Mid–40 lidar with a conic field of view extended by a custom rotating planar reflector. This 3D sensor is compared with the more expensive Velodyne VLP 16 lidar. It is shown that the proposed sensor reaches satisfactory accuracy and range. Furthermore, it is able to preserve the metric accuracy and non–repetitive scanning pattern of the unmodified sensor. Due to preserving the non–repetitive scan pattern, our system is capable of covering the entire field of view of 38.4 × 360 degrees, which is an added value of conducted research. We show the calibration method, mechanical design, and synchronization details that are necessary to replicate our system. This work extends the applicability of solid–state lidars since the field of view can be reshaped with minimal loss of measurement properties. The solution was part of a system that was evaluated during the 3rd European Robotics Hackathon in the Zwentendorf Nuclear Power Plant. The experimental part of the paper demonstrates that our affordable robotic mobile 3D mapping system is capable of providing 3D maps of a nuclear facility that are comparable to the more expensive solution. [ABSTRACT FROM AUTHOR]

Teams of mobile robots can be employed in many outdoor applications, such as precision agriculture, search and rescue, and industrial inspection, allowing an efficient and robust exploration of large areas and enhancing the operators' situational awareness. In this context, this paper describes an active and decentralized framework for the collaborative 3D mapping of large outdoor areas using a team of mobile ground robots under limited communication range and bandwidth. A real-time method is proposed that allows the sharing and registration of individual local maps, obtained from 3D LiDAR measurements, to build a global representation of the environment. A conditional peer-to-peer communication strategy is used to share information over long-range and short-range distances while considering the bandwidth constraints. Results from both real-world and simulated experiments, executed in an actual solar power plant and in its digital twin representation, demonstrate the reliability and efficiency of the proposed decentralized framework for such large outdoor operations. [ABSTRACT FROM AUTHOR]

Introduction: Variability of the bipolar atrial electrogram amplitude may affect voltage maps created during ablation procedures, and thus also the extent of ablations. Therefore, the aim of the study was to assess the beat‐to‐beat electrogram amplitude variability in the left atrium in patients undergoing atrial fibrillation ablation. Methods: In 11 patients undergoing ablation for atrial fibrillation, 362 mapping points were collected in two series. At each point, three consecutive beats were recorded and verified including the bipolar electrogram amplitude, contact force (CF), and orientation of the catheter tip. The repeatability and reproducibility of obtained measurements between consecutive beats and series were assessed by the Pearson correlation coefficient (r), the Bland‐Altman test, repeatability coefficient (RC), relative standard deviation (RSD), and concordance correlation coefficient (CCC). Results: A total of 1086 beats were analyzed. The correlation coefficient for bipolar atrial electrogram amplitude for the first two beats, and for the first and the third beats were 0.94 and 0.86, respectively. The average of differences between the first two beats and between the first and the third beats were 0.06 and 0.13 mV with 95% limits of agreement (LoA) within ±0.98 and ±1.74 mV, respectively. For CF values ≤5 and ≥20 g, the 95% LoA were narrower compared to other CF ranges and were ±0.49 and ±0.71 mV from the average value, respectively. When the analyzes were performed within the predefined ranges of bipolar electrogram amplitude: 0.05–1; 1–2; 2–3 mV, the 95% LoA were within ±0.33, ±0.98, and ±0.84 mV from the average value, respectively. RC and RSD were 1.41 mV and 20.8%, respectively. For repeated measurement between series, CCC ranged from 0.67 to 0.71 and the 95% LoA were within ±2.7 to 2.9 mV from the average value. Conclusion: Bipolar atrial electrogram amplitude recorded at a given site during ablation procedures is variable to an extent that may be clinically relevant. The magnitude of the observed variability is greater during remapping. [ABSTRACT FROM AUTHOR]

A High-Definition (HD) map is an essential component not only for autonomous vehicles but also for surveyors in favor of city management. Moreover, the HD map must be up-to-date by reflecting environmental changes continuously. The development of LiDAR Simultaneous Localization And Mapping (SLAM) techniques has provided an effective way to collect precise point clouds for the construction of HD maps, while traditional methods are time-consuming and labor-intensive on account of the complex street scene. Furthermore, life-long 3D mapping is quite necessary and challenging nowadays. In this paper, we introduce a novel change-aware 3D online mapping framework CAOM, 1 1 Code at https://github.com/DCSI2022/CAOM. using point clouds collected by Multi-Beam LiDAR (MBL) and Push-Broom LiDAR (PBL) for rapid city map update and change detection. Concerning the prior map with higher precision, heterogenous fusion is performed to rectify the SLAM drift, based on the View-Traced Clouds (ViTC) derived according to their view in common. Meanwhile, corresponding virtual range images are integrated with distance images to detect the 3D changes between the current map and the historical reference map offline. The detection results are later fused in a probabilistic way along with the homogeneous fusion process where a resilient graph consisting of diverse factors is established to maintain the local and global consistency of the final point cloud map. Compared with 3D-CSTM, the real-world experiments have shown an average 0.5 m and max 1.5 m improvement in the ATE (Absolute Translation Error) of the trajectory generated by our system. Quantitative measurements on the individual point accuracy are also conducted to verify the performance of 3D mapping with up to 16% improvement in comparison with respect to the 3D-CSTM method. The effects of the disparity detection and probabilistic fusion can be revealed from the small objects distinguished in the point cloud map as well as > 95% overall accuracy. [ABSTRACT FROM AUTHOR]

3D maps are one of the most attractive cartographical products for map users. They can present the real environment in a photorealistic, readable way, keeping enough geo-spatial information for the needs of different users. Very often users don't make a difference between 3D maps and 3D models of the real environment. The aim of this report is to clarify when we can speak of 3D maps and even to discuss the definition of a 3D map. The article considers the cartographical elements applied in 3D mapping which help a 3D model to become a 3D map: user requirements, map contents, symbol system, accuracy, scale, projections and generalization, levels of details. The new cartographical elements are added to improve 3D maps: virtual camera, shades, lights, animation. In conclusion, the author will explain when we can speak of a 3D model and when of a 3D map. [ABSTRACT FROM AUTHOR]

In computer vision, stereoscopy allows the three-dimensional reconstruction of a scene using two 2D images taken from two slightly different points of view, to extract spatial information on the depth of the scene in the form of a map of disparities. In stereophotogrammetry, the disparity map is essential in extracting the digital terrain model (DTM) and thus obtaining a 3D spatial mapping, which is necessary for a better analysis of planetary surfaces. However, the entire reconstruction process performed with the stereo-matching algorithm can be time consuming and can generate many artifacts. Coupled with the lack of adequate stereo coverage, it can pose a significant obstacle to 3D planetary mapping. Recently, many deep learning architectures have been proposed for monocular depth estimation, which aspires to predict the third dimension given a single 2D image, with considerable advantages thanks to the simplification of the reconstruction problem, leading to a significant increase in interest in deep models for the generation of super-resolution images and DTM estimation. In this paper, we combine these last two concepts into a single end-to-end model and introduce a new generative adversarial network solution that estimates the DTM at 4× resolution from a single monocular image, called SRDiNet (super-resolution depth image network). Furthermore, we introduce a sub-network able to apply a refinement using interpolated input images to better enhance the fine details of the final product, and we demonstrate the effectiveness of its benefits through three different versions of the proposal: SRDiNet with GAN approach, SRDiNet without adversarial network, and SRDiNet without the refinement learned network plus GAN approach. The results of Oxia Planum (the landing site of the European Space Agency's Rosalind Franklin ExoMars rover 2023) are reported, applying the best model along all Oxia Planum tiles and releasing a 3D product enhanced by 4 × . [ABSTRACT FROM AUTHOR]

This paper presents a real-time object-based 3D change detection method that is built around the concept of semantic object maps. The algorithm is able to maintain an object-oriented metric-semantic map of the environment and can detect object-level changes between consecutive patrol routes. The proposed 3D change detection method exploits the capabilities of the novel ZED 2 stereo camera, which integrates stereo vision and artificial intelligence (AI) to enable the development of spatial AI applications. To design the change detection algorithm and set its parameters, an extensive evaluation of the ZED 2 camera was carried out with respect to depth accuracy and consistency, visual tracking and relocalization accuracy and object detection performance. The outcomes of these findings are reported in the paper. Moreover, the utility of the proposed object-based 3D change detection is shown in real-world indoor and outdoor experiments. [ABSTRACT FROM AUTHOR]

Background: To clarify the injury mechanism of the avulsion fracture of the fifth metatarsal combining 3-dimensional (3D) fracture mapping with anatomical measurements. Methods: Two hundred twenty-two patients with the avulsion fractures of the fifth metatarsal base, who were admitted to our hospital from August 2015 to August 2020. The computed tomography (CT) scans were used to generate the 3-D images of all mapped fracture lines for the avulsion fractures of the fifth metatarsal base were compiled in an overall 3D image. The fifth metatarsal base of 8 unpaired lower limbs of adult Asian frozen cadaveric specimens were also dissected to observe and measure the specific locations of the attachment points of the peroneus brevis, lateral band of the plantar fascia, and peroneus tertius to the fifth metatarsal base. Results: Based on the type of fracture line produced and the specific locations of the attachment points of the tendons or fascia, the avulsion fractures of the fifth metatarsal base can be classified into three types: type I predominantly involves the action of the lateral band of the plantar fascia; type II predominantly involves the action of the peroneus brevis; type IIIA involves the joint action of the peroneus brevis and lateral band of the plantar fascia with one fracture line, and type IIIB involves the joint action of the peroneus brevis and lateral band of the plantar fascia with two fracture lines. Conclusion: The lateral band of the plantar fascia and peroneus brevis play a major role, either separately or together, in avulsion fractures of the fifth metatarsal base. With this knowledge, we propose a novel classification based on the injury mechanism, which can serve as a reference for clinical treatment and diagnosis. Level of evidence: Level III, retrospective case series. [ABSTRACT FROM AUTHOR]

Introduction: Ablation for atrioventricular nodal reentrant tachycardia (AVNRT) classically utilizes evaluation of signal morphology within the anatomic region of the slow pathway (SP), which involves subjectivity. Ripple mapping (RM; CARTO‐3© Biosense Webster Inc) displays each electrogram at its three‐dimensional coordinate as a bar changing in length according to its voltage–time relationship. This allows prolonged, low‐amplitude signals to be displayed in their entirety, helping identify propagation in low‐voltage areas. We set out to evaluate the ability of RM to locate the anatomic site of the SP and assess its use in guiding ablation for AVNRT. Methods: Patients ≤18 years with AVNRT in the EP laboratory between 2017 and 2021 were evaluated. RM was performed to define region of SP conduction in patients from 2019 to 2021, whereas standard electro‐anatomical mapping was used from 2017 to 2019. All ablations were performed using cryotherapy. Demographics, outcomes, and analysis of variance in number of test lesions until success was compared between groups. Results: A total of 115 patients underwent AVRNT ablation during the study; 46 patients were in the RM group and 69 were in the control group. There were no demographic differences between groups. All procedures, in both groups, were acutely successful. In RM group, 89% of first successful lesions were within 4 mm of the predicted site. There was significantly reduced variability in number of test lesions until success in the RM group (p =.01). Conclusion: RM is a novel technique that can help identify SP location, allowing for successful ablation of AVNRT with decreased variability. [ABSTRACT FROM AUTHOR]

Tunnel surveys making use of photogrammetric three‐dimensional (3D) tunnel reconstruction reach resolutions in the millimeter range. Classical big data visualization approaches display point clouds only, neglecting this considerable resolution difference between structure and texture. The article suggests a data structure that separates structural and textural resolution by a regular grid on the unwrapped design surface for 3D, combined with a UV mapping technique as regularly used in computer graphics. For real‐time rendering of huge multiscale data sets, the result of photogrammetric commercial‐off‐the‐shelf reconstructions is transformed into a proprietary hierarchical data structure. It facilitates to only load currently relevant parts of the tunnel surface from the hard drive, and only upload and render currently adequate levels‐of‐detail onto the graphics card for seamless exploration of high‐resolution geometric and image 3D tunnel data of arbitrary length. The solution allows for smooth interactive analysis and annotation such as crack identification and mapping, inventory, deformation assessment, and dimensional measurements. Aspects of data generation are addressed and information is given about the data structure, showing examples from entire tunnel 3D representations to demonstrate the smooth behaviour of the real‐time rendering of huge data volumes in various scales on standard graphics hardware. [ABSTRACT FROM AUTHOR]

This work presents a methodology for horizontal soil stratification and a device for 3D soil mapping using the discretization of the Wenner's method. The methodology starts from the application of the lateral profiling method in conjunction with the Wenner's method to find the experimental resistivity curve. The Sunde's algorithm is used to construct the theoretical resistivity curve. By utilizing these experimental and theoretical resistivity curves, it is possible to apply the optimization process to find the parameters: electrical conductivity and thickness of each soil layer. The area under study is discretized and the results related to all subareas are unified using interpolation process. The whole process which results in 3D soil mapping may be automatically produced using the proposed device. [ABSTRACT FROM AUTHOR]

An 84‐year‐old woman with type B Wolff–Parkinson–White (WPW) with Ebstein anomaly was admitted with heart failure. She had rapid wide QRS tachycardia due to accessory pathway (AP) conduction associated with atrial fibrillation (AF). Since transesophageal echocardiography before catheter ablation showed a left atrial thrombus, ablation was performed using a 3D mapping system under AF. After marking the functional tricuspid anulus with intra‐cardiac echocardiography, 3D intra‐cardiac electrogram visualization (ripple map) during AF enabled clear identification of location of the AP. After ablation, there was no complication of cerebral infarction, and the heart failure improved. [ABSTRACT FROM AUTHOR]

Introduction: His bundle pacing (HBP) and left bundle branch area pacing (LBBAP) have emerged as attractive alternatives to traditional biventricular pacing to achieve cardiac resynchronization therapy. Early reported results have been inconsistent, particularly amongst patients in whom initial placement with traditional approaches has been unsuccessful or those with complex anatomy or congenital abnormalities. In this report, we describe the use of three‐dimensional electroanatomic mapping (EAM) in five selected cases. Methods: Five patients from multiple clinical sites underwent EAM‐guided HBP or LBBAP by highly trained electrophysiologists with significant experience with conduction system pacing. Each patient in this series underwent EAM‐guided conduction system pacing due to complex anatomy and/or prior failed lead implantation. Results: EAM‐guided lead implantation was successful in all five cases. Capture thresholds were relatively low and patients continued to have evidence of successful lead implantation with minimum 1‐month follow‐up. The fluoroscopy time varied, likely owing to the variable complexity of the cases. Conclusions: The use of EAM, in combination with traditional intracardiac electrograms with or without fluoroscopy, allows more targeted and precise placement of leads for HBP and LBBAP pacing. Further investigation is needed to determine this strategy's long‐term performance and to optimize patient selection. [ABSTRACT FROM AUTHOR]

This paper briefly introduces the background, significance, and development status of 3D radar technology at home and abroad, and then explains the concept, working principle, system composition, and workflow of the radar system. Combined with the current development trend of smart grids, it focuses on the application scope of this technology in the field of transmission line construction, operation, and maintenance. Then, through the specific implementation of the project cases, the daily operation and maintenance of four 500 kV transmission lines in Nanjing have played a certain guiding role. Finally, according to the development trend of smart grid and the actual demand of power system production and business integration, this paper briefly prospects the function expansion of this technology in transmission line operation evaluation, fault analysis and diagnosis, emergency rescue plan formulation, and other fields. [ABSTRACT FROM AUTHOR]

Summary: Currently, both the heated building area and total pipe length have been increased significantly. Despite the rapid development of China's heating industry, the overall efficiency of district heating systems is relatively low. In this paper, an innovative smart and transparent heating mode is proposed to solve the problems of the current heating mode. The proposed method integrates two core technologies: the 3D‐GIS digital twin model and the NB‐IoT wireless communication system. The concept, main characteristic of the proposed heating mode is discussed. A concrete technical scheme of the heating mode integrating the static and dynamic data of DHN is presented. To test the feasibility and effectiveness of the proposed heating mode, two cases with a concrete implementation scheme are presented. The energy reduction rate, pump efficiency, and hydraulic imbalance level of proposed heating mode is compared with the traditional heating mode. Results show that the energy consumption of DHN under traditional set secondary‐side supply target temperature control mode can be reduced by 26.11% compared with smart and transparent heating mode during the heating period. [ABSTRACT FROM AUTHOR]

GNSS services and new applications are growing but alternative systems are being studied in parallel. Together with their diffusion in all the critical infrastructures of our society, the awareness is growing that the current GNSS constellations (GPS, GLONASS, Galileo and Beidou) are not completely sufficient to guarantee efficient and safe services. "Jamming" and "spoofing" are increasingly real threats. Alternatives, largely based on terrestrial systems, such as E-Loran, or platforms based on the integration of various sensors (for example inertial ones) with GNSS receivers, are in progress to be studied. [ABSTRACT FROM AUTHOR]

The article discusses the possible prediction of right atrial flutter via constant pacing on collision of the two wavefronts on the lateral wall of the right atrium. Topics covered include the use of right atrial collision time (RACT) as a marker for development of typical atrial flutter (AFL), and the non-association of larger right/left atrial volumes on AFL development. Also noted is the association of comorbidities like systemic hypertension with AFL patients.

Autism spectrum disorder (ASD) is a name for a group of neurodevelopmental conditions that are characterized by some degree of impairment in social interaction, verbal and non-verbal communication, and difficulty in symbolic capacity and repetitive behaviors. The only protocol followed currently for ASD diagnosis is the qualitative behavioral assessment by experts through internationally established descriptive scaling standards. The assessment can, therefore, be affected by the degree of the evaluator experience as well as by the level of the descriptive standard robustness. This paper presents an EEG-based quantitative approach intended for automatic discrimination between children with typical neurodevelopment and children with ASD. The suggested work relies on second-order difference plot (SODP) area as a discriminative feature: First, every EEG channel in a 64 electrode cap—for every volunteer—is decomposed into intrinsic mode functions (IMFs) by empirical mode decomposition (EMD). Next, the second-order difference plot for the first ten intrinsic mode functions—of every channel—is sketched. Third, the value of the elliptical area —for every plot—is calculated. The 95% confidence ellipse area is used as the discriminative feature. Fourth, paired t-student test is applied to the vectors consisting of discriminative feature values for counterpart channels/IMFs (e.g., channel FPz/IMF7 in autistic and neurotypical) for all volunteers. Finally, principal component analysis (PCA) and neural network (NN) are applied to the SODP area feature matrix for two-class classification (ASD and neurotypical). Moreover, the 3D mapping of EEG SODP area values was implemented and analyzed. The obtained results show that the conducted t-student tests yield values of less than 0.05, and that the NN two-class classification based on SODP features leads to a 94.4% accuracy, which indicates significant differences between SODP area values of children with neurotypical development and those diagnosed with ASD. The obtained results have also been emphasized by the analysis of the findings of the performed 3D mapping. [ABSTRACT FROM AUTHOR]

Tissue optical clearing techniques have provided important tools for large‐volume imaging. Aqueous‐based clearing methods are known for good fluorescence preservation and scalable size maintenance, but are limited by long incubation time, insufficient clearing performance, or requirements for specialized devices. Additionally, few clearing methods are compatible with widely used lipophilic dyes while maintaining high clearing performance. Here, to address these issues, m‐xylylenediamine (MXDA) is firstly introduced into tissue clearing and used to develop a rapid, highly efficient aqueous clearing method with robust lipophilic dyes compatibility, termed MXDA‐based Aqueous Clearing System (MACS). MACS can render whole adult brains highly transparent within 2.5 days and is also applicable for other intact organs. Meanwhile, MACS possesses ideal compatibility with multiple probes, especially for lipophilic dyes. MACS achieves 3D imaging of the intact neural structures labeled by various techniques. Combining MACS with DiI labeling, MACS allows reconstruction of the detailed vascular structures of various organs and generates 3D pathology of glomeruli tufts in healthy and diabetic kidneys. Therefore, MACS provides a useful method for 3D mapping of intact tissues and is expected to facilitate morphological, physiological, and pathological studies of various organs. [ABSTRACT FROM AUTHOR]

This review paper explores at a high conceptual level cartography's potential role in the emerging field of indoor mapping. It introduces an interdisciplinary literature on foundational theories, approaches, and applications of indoor maps driven by advancements in indoor positioning systems and an accompanying desire to exploit those capabilities through maps. The review concludes that cartography, with its rich heritage in the mapping arts and sciences, can make important contributions as technologies, needs, and theories converge to make sophisticated indoor mapping a reality. This paper includes discussions of issues, challenges, and prospects for indoor mapping along with examples of possible new applications. [ABSTRACT FROM AUTHOR]

Summary: In this paper, we propose a method of using an autonomous flying robot to explore an underground tunnel environment and build a 3D map. The robot model we use is an extension of a 2D non-holonomic robot. The measurements and sensors we considered in the presented method are simple and valid in practical unmanned aerial vehicle (UAV) engineering. The proposed safe exploration algorithm belongs to a class of probabilistic area search, and with a mathematical proof, the performance of the algorithm is analysed. Based on the algorithm, we also propose a sliding control law to apply the algorithm to a real quadcopter in experiments. In the presented experiment, we use a DJI Guidance sensing system and an Intel depth camera to complete the localization, obstacle detection and 3D environment information capture. Furthermore, the simulations show that the algorithm can be implemented in sloping tunnels and with multiple UAVs. [ABSTRACT FROM AUTHOR]

This article tackles the problem of designing 3D perception systems for robots with high visual requirements, such as versatile legged robots capable of different locomotion styles. In order to guarantee high visual coverage in varied conditions (e.g., biped walking, quadruped walking, ladder climbing), such robots need to be equipped with a large number of sensors, while at the same time managing the computational requirements that arise from such a system. We tackle this problem at both levels: sensor placement (how many sensors to install on the robot and where) and run-time acquisition scheduling under computational constraints (not all sensors can be acquired and processed at the same time). Our first contribution is a methodology for designing perception systems with a large number of depth sensors scattered throughout the links of a robot, using multi-objective optimization for optimal trade-offs between visual coverage and the number of sensors. We estimate the Pareto front of these objectives through evolutionary optimization, and implement a solution on a real legged robot. Our formulation includes constraints on task-specific coverage and design symmetry, which lead to reliable coverage and fast convergence of the optimization problem. Our second contribution is an algorithm for lowering the computational burden of mapping with such a high number of sensors, formulated as an information-maximization problem with several sampling techniques for speed. Our final system uses 20 depth sensors scattered throughout the robot, which can either be acquired simultaneously or optimally scheduled for low CPU usage while maximizing mapping quality. We show that, when compared with state-of-the-art robotic platforms, our system has higher coverage across a higher number of tasks, thus being suitable for challenging environments and versatile robots. We also demonstrate that our scheduling algorithm allows higher mapping performance to be obtained than with naïve and state-of-the-art methods by leveraging on measures of information gain and self-occlusion at low computational costs. [ABSTRACT FROM AUTHOR]

Ecological processes occur over multiple spatial, temporal and thematic scales in three-dimensional (3D) ecosystems. Characterizing and monitoring change in 3D structure at multiple scales is challenging within the practical constraints of conventional ecological tools. Remote sensing from satellites and crewed aircraft has revolutionized broad-scale spatial ecology, but fine-scale patterns and processes operating at sub-metre resolution have remained understudied over continuous extents. We introduce two high-resolution remote sensing tools for rapid and accurate 3D mapping in ecology—terrestrial laser scanning and structure-from-motion photogrammetry. These technologies are likely to become standard sampling tools for mapping and monitoring 3D ecosystem structure across currently under-sampled scales. We present practical guidance in the use of the tools and address barriers to widespread adoption, including testing the accuracy of structure-from-motion models for ecologists. We aim to highlight a new era in spatial ecology that uses high-resolution remote sensing to interrogate 3D digital ecosystems. [ABSTRACT FROM AUTHOR]

Building 3D maps of surroundings is a fundamental and important task for autonomous robots operating in large previously unknown semi-structured or unstructured outdoor environments, where external methods for localization like GPS are not always available. Most of existing 3D mapping approaches are based on the local scan matching algorithm, which are difficult to achieve accurate mapping with good efficiency. In this paper, we propose an effective graph-based SLAM approach for 3D mapping of outdoor environments without odometry measurement. It first utilizes scan matching algorithm to sequentially estimate initial robot poses and progressively construct a pose graph, where each vertex denotes the robot pose at a point in time and each edge indicates the constraint between two robot poses. As scan matching algorithm cannot be error-free, the estimation of robot poses suffers from the error accumulation problem. To address this issue, the hypothesis of loop closure can be generated by an adaptive search circle and then verified by the global scan matching algorithm. Once the loop closure is verified, more edges should be added into the pose graph, which is subsequently optimized by the weighted motion averaging algorithm so as to obtain accurate robot poses for 3D mapping. Experimental results carried out on multiple outdoor environment data sets show that the proposed approach can build 3D maps with good performance. [ABSTRACT FROM AUTHOR]

Introduction: Permanent His bundle pacing is feasible and effective in patients with atrioventricular block or left bundle branch block. However, pacing thresholds to capture the distal His bundle is often higher. Recently left bundle branch area pacing (LBBP) has been shown to be feasible by advancing the lead transvenously, deep into the interventricular septum to reach the left ventricular endocardial surface. In this article we describe the utility of three dimensional (3D) mapping to achieve LBBP. Methods: Ensite Precision (Abbott) mapping system was used to perform LBBP. A decapolar catheter was used to create 3D map of right atrium and right ventricle (RV). Regions of interest (His bundle, potential LBBP sites of interest in RV) were tagged in the 3D map. The LBBP lead was implanted utilizing the 3D map. The lead depth in the septum was assessed in the 3D map. Results: LBBP was performed in three patients: chronic LBBB and intermittent 2:1 atrioventricular block; atrioventricular (AV) node ablation and conduction system pacing; and bifascicular block and intermittent AV block in a patient with severe left ventricular hypertrophy. LBBP was successful in all three patients. The lead depth in the interventricular septum was 12, 11, and 21 mm, respectively as assessed by 3D mapping. Conclusions: Three‐dimensional mapping was helpful in achieving LBBP in patients with LBBB, severe left ventricular hypertrophy or during AV node ablation. 3D mapping also facilitated easy assessment of lead depth during and after lead fixation. 3D mapping techniques may be a valuable tool to reduce the learning curve of implanters with minimal experience in LBBP. [ABSTRACT FROM AUTHOR]

Fine scale maps of soil properties enable efficient land management and inform earth system models. Recent efforts to create soil property maps from field observations tend to use similar tree-based machine learning interpolation approaches, but often deal with depth of predictions, validation, and uncertainty differently. One of the main differences in approaches is whether to model individual depths of interest separately as '2D' models, or to create models that incorporate depth as a predictor variable creating a '3D' model that can make predictions for all depths. It is unclear how choice of 2D or 3D approach influences model accuracy and uncertainty due to lack of direct comparison and inconsistent presentation of results in past studies. This study compares 2D and 3D methods for mapping soil electrical conductivity (salinity), pH, sum of fine and very fine sands, and organic carbon at 30 m resolution for the upper 432,000 km2 of the Colorado River Watershed of the United States of America. A new, simple, model-agnostic relative prediction interval (RPI) approach to report uncertainty is presented that scales prediction interval width to the 95% interquantile width of the original training sample distribution. The RPI approach enables direct comparison of uncertainty between properties and depths and is easily interpretable by end users. Results indicate that 3D mapping of soil properties with strong variation with depth can result in substantial areas with much higher uncertainty that coincide with unrealistic predictions relative to 2D models, even though 3D models had slightly better global cross-validation scores. Maps and global model summaries of RPI proved helpful in identifying these issues with 3D models. These results suggest that the use of RPI or similar approaches to evaluate models can identify accuracy problems not evident in global validation diagnostics. • Created maps of soil salinity, pH, texture, and organic carbon at 30 m resolution • Predictive mapping using 2D and 3D approaches have similar cross-validation accuracies. • Relative prediction interval approach developed to help interpret uncertainty. • Predictive 3D soil spatial mapping models can produce areas of very high uncertainty. [ABSTRACT FROM AUTHOR]

The presence of dynamic objects (DO) affect the mobility of the visually impaired people (VIP) and so it is important to indicate the safest areas to move in. This article presents a new methodology for detecting and tracking DO to reproduce their paths. This methodology consists of: a requirements analysis specific to the context of the VIP; the development of four architectures adapted to the VIP; the generation of a 3D map composed of paths made by DO; and a comparative analysis between the architectures in order to obtain the best solution from the union of the best characteristics detected. These architectures, the main adaptations being related to the factors of illumination and movement undergone by the acquisition sensors that can interfere with the process of DO segmentation. Experiments were performed in different environments with the absence and presence of movement of the acquisition sensors. [ABSTRACT FROM AUTHOR]

The article presents the discussion on ablation of ventricular tachycardia (VT) showing to reduce VT recurrence. Topics include randomised trial of patients with ischaemic cardiomyopathy having better results with extensive substrate modification compared to conventional VT mapping and ablation; and Ripple Mapping being superior to conventional activation mapping in atrial tachycardias.