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Individuals with DS develop Alzheimer's disease (AD) neuropathology, including endosomal-lysosomal system abnormalities and degeneration of basal forebrain cholinergic neurons (BFCNs). We investigated whether maternal choline supplementation (MCS) affects early endosome pathology within BFCNs using the Ts65Dn mouse model of DS/AD. Ts65Dn and disomic (2N) offspring from dams administered MCS were analyzed for endosomal pathology at 3–4 months or 10–12 months. Morphometric analysis of early endosome phenotype was performed on individual BFCNs using Imaris. The effects of MCS on the endosomal interactome were interrogated by relative co-expression (RCE) analysis. MCS effectively reduced age- and genotype-associated increases in early endosome number in Ts65Dn and 2N offspring, and prevented increases in early endosome size in Ts65Dn offspring. RCE revealed a loss of interactome cooperativity among endosome genes in Ts65Dn offspring that was restored by MCS. These findings demonstrate MCS rescues early endosome pathology, a driver of septohippocampal circuit dysfunction. The genotype-independent benefits of MCS on endosomal phenotype indicate translational applicability as an early-life therapy for DS as well as other neurodevelopmental/neurodegenerative disorders involving endosomal pathology. • Evaluated maternal choline supplementation in a murine model of DS/AD. • MCS decreases early endosome pathology in trisomic offspring. • MCS attenuates age-associated increases in early endosome number in BFCNs. • MCS restores early endosome interactome connectivity. [ABSTRACT FROM AUTHOR]

Background: With the increasing number of surgeries utilizing spinal instrumentation, three-dimensional surgical navigation aims to improve the accuracy of implant placement. However, its widespread clinical adaption has been hindered by factors such as high radiation exposure and interference with standard surgical workflows. Methods: X23D is a novel AI-based fluoroscopy reconstruction technique that generates a 3D anatomical model of the spine from only four fluoroscopy images. Based on this technology, we developed a prototype for the surgical navigation of pedicle screws placement of the lumbar spine, visualizing the 3D-reconstructed spine anatomy and the surgical drill position in real-time. An ex-vivo study was conducted to compare the accuracy of the X23D-based navigation approach with fluoroscopy-aided freehand instrumentation. Five board-certified surgeons placed pedicle screws on six human torsi within a realistic surgical environment. Breach rate, site and extent (Gertzbein-Robbins) were evaluated in postoperative CT scans, as well as execution time, radiation dose, and user experience. Specimens, operating side, and surgeon were randomised. Results: Forty-nine pedicle screws (n = 24 × 23D, n = 25 2D-fluoroscopy) were evaluated, with six breaches occurring in the control group, one of which was considered clinically significant (medial breach grade C). Five breaches with one clinically significant breach were observed in the X23D group. Breach rate, execution time for each lumbar level (X23D 167 s vs. control 156 s), radiation dose (X23D 33.26 mGy vs. control 49.5 mGy), and user experience did not reveal significant differences (p > 0.05) between the groups. Conclusions: Spinal navigation using the X23D-based approach shows promise and performs well in a realistic surgical ex-vivo setting. With further refinements, its accuracy is expected to match clinical-grade navigation systems while reducing radiation dose. [ABSTRACT FROM AUTHOR]

The oviduct plays a crucial role in the reproductive process, serving as the stage for fertilization and the early stages of embryonic development. When the environment of this organ has been mimicked, it has been shown to enhance in vitro embryo epigenetic reprogramming and to improve the yield of the system. This study explores the anatomical intricacies of two oviduct regions, the uterotubal junction (UTJ) and the ampullary-isthmic junction (AIJ) by using micro-computed tomography (MicroCT). In this study, we have characterized and 3D-reconstructed the oviduct structure, by measuring height and width of the oviduct's folds, along with the assessments of fractal dimension, lacunarity and shape factor. Results indicate distinct structural features in UTJ and AIJ, with UTJ displaying small, uniformly distributed folds and high lacunarity, while AIJ shows larger folds with lower lacunarity. Fractal dimension analysis reveals values for UTJ within 1.189-1.1779, while AIJ values range from 1.559-1.770, indicating differences in structural complexity between these regions. Additionally, blind sacs or crypts are observed, akin to those found in various species, suggesting potential roles in sperm sequestration or reservoir formation. These morphological differences align with functional variations and are essential for developing an accurate 3D model. In conclusion, this research provides information about the oviduct anatomy, leveraging MicroCT technology for detailed 3D reconstructions, which can significantly contribute to the understanding of geometric-morphological characteristics influencing functional traits, providing a foundation for a biomimetic oviduct-on-a-chip. [ABSTRACT FROM AUTHOR]

Calcareous skeletal structures are common among different invertebrate groups, including Porifera, Cnidaria, Platyhelminthes, Mollusca, and Echinodermata. They appear externally as shells, plates, or scales, or internally as subepidermal spicules. Although typically formed outside of the cells, in one class of gastropod molluscs, the Heterobranchia, subepidermal and intracellular spicules are found—a rare case, at least for the molluscs. This type of spicules is present in several phylogenetically distant groups of heterobranch molluscs (Rhodopemorpha, Acochlidimorpha, and Nudibranchia), each different in terms of morphology and autecology. This raises questions about the origin and homology of subepidermal spicules in heterobranch molluscs. To answer these questions, understanding the process of spicule formation is crucial. This is impeded by insufficient data on the fine structure of the subepidermal spicules and adjacent epithelia. To address this problem, we carried out a comprehensive morphological study of subepidermal spicules and the body wall in one species of Acochlidimorpha. We revealed variations in the cellular composition of the epidermis, musculature organization, and spicules' arrangement, which most likely reflect the different functional roles of the spicule complex within Heterobranchia representatives. However, the obtained data are insufficient to answer the question of the origin of spicules and their homology within Heterobranchia. [ABSTRACT FROM AUTHOR]

The oviduct plays a crucial role in the reproductive process, serving as the stage for fertilization and the early stages of embryonic development. When the environment of this organ has been mimicked, it has been shown to enhance in vitro embryo epigenetic reprogramming and to improve the yield of the system. This study explores the anatomical intricacies of two oviduct regions, the uterotubal junction (UTJ) and the ampullary-isthmic junction (AIJ) by using micro-computed tomography (MicroCT). In this study, we have characterized and 3D-reconstructed the oviduct structure, by measuring height and width of the oviduct’s folds, along with the assessments of fractal dimension, lacunarity and shape factor. Results indicate distinct structural features in UTJ and AIJ, with UTJ displaying small, uniformly distributed folds and high lacunarity, while AIJ shows larger folds with lower lacunarity. Fractal dimension analysis reveals values for UTJ within 1.189–1.1779, while AIJ values range from 1.559–1.770, indicating differences in structural complexity between these regions. Additionally, blind sacs or crypts are observed, akin to those found in various species, suggesting potential roles in sperm sequestration or reservoir formation. These morphological differences align with functional variations and are essential for developing an accurate 3D model. In conclusion, this research provides information about the oviduct anatomy, leveraging MicroCT technology for detailed 3D reconstructions, which can significantly contribute to the understanding of geometric-morphological characteristics influencing functional traits, providing a foundation for a biomimetic oviduct-on-a-chip.

In this study, we investigate the performance of axial-conical lenses, commonly referred to as Powell lenses, featuring varying fan angles of 5°, 7.5°, 10°, 15°, and 20°. Our objective is to evaluate their suitability for designing a light sheet generator tailored for fluorescence light-sheet microscopy of large samples. Our results indicate that Powell lenses with fan angles of 5° and 7.5° when integrated with additional aspheric components, exhibit optimal characteristics for this application. Specifically, employing a Powell lens with a 7.5° fan angle and 0.2 mm roundness at the tip facilitates the generation of a light sheet ideal for illuminating samples within a size range of 2,000 µm–15,000 µm. To validate the practicality of our optical design for real-world imaging tasks, we conducted imaging experiments on chicken embryos aged between 3 and 7 days. Our light-sheet microscopy system successfully captured intricate structural details, particularly highlighting the ongoing differentiation of the inner anatomy of these specimens. This approach has a high potential to improve the screening of pharmaceutical drugs acting on the vascularization of the chorioallantois membrane (CAM), a technique that is widely used in pharmaceutical research. [ABSTRACT FROM AUTHOR]

In various fields, such as robotics navigation, autonomous driving, and augmented reality, the demand for the reconstructing of three-dimensional (3D) scenes from two-dimensional (2D) images captured by a camera is growing. With advancements in deep learning, monocular depth prediction research has gained momentum, leading to the exploration of 3D reconstruction from a single image. While previous studies have attempted to restore occluded regions by training deep networks on high-resolution 3D data or with jointly learned 3D segmentation, achieving perfect restoration of occluded objects remains challenging. Such 3D mesh generation methods often result in unrealistic interactions with graphic objects, limiting their applicability. To address this, this paper introduces an amodal depth estimation approach to enhance the completeness of 3D reconstruction. By utilizing amodal masks that recover occluded regions, the method predicts the depths of obscured areas. Employing an iterative amodal depth estimation framework allows this approach to work even with scenes containing deep occlusions. Incorporating a spatially-adaptive normalization (SPADE) fusion block within the amodal depth estimation model effectively combines amodal mask features and image features to improve the accuracy of depth estimation for occluded regions. The proposed system exhibits superior performance on occluded region depth estimation tasks compared to conventional depth inpainting networks. Unlike models that explicitly rely on multiple RGB or depth images to handle instances of occlusion, the proposed model implicitly extracts amodal depth information from a single image. Consequently, it significantly enhances the quality of 3D reconstruction even when single images serve as input. The code and data used in the paper are available at https://github.com/Seonguke/Occlusion-aware-Amodal-Depth-Estimation-for-Enhancing-3D-Reconstruction-from-a-Single-Image/ for further research and feedback.

Palais Rihour in Lille, built for Philip the Good, duke of Burgundy, was an ambitious and influential architectural project that redefined princely magnificence in the 15th century. Despite its significance for court architecture in Northern Europe and Spain, the building has only recently garnered scholarly attention. Its destruction has hindered a comprehensive understanding of its interior. This article presents a meticulous analysis of the great hall and 'sallette' in the north-west wing of Rihour based on new empirical data. By combining detailed building specifications, archival data, and visual sources, a reliable reconstruction of the original design has been achieved. Close examination of drawings depicting later modifications and restorations has been crucial in establishing the connection between the great hall and the overall structure. Utilizing these sources, a Critical Digital Model of the north-west wing has been developed, enhancing the visual impact and spatial organization. However, the aim is not to create an attractive but undocumented reconstruction; instead, the model's accuracy is authenticated and the interpretation traceable through comprehensive documentation of all sources and design choices in a metafile (linked at the end). [ABSTRACT FROM AUTHOR]

Today, human gait analysis is commonly used for clinical diagnosis, rehabilitation and performance improvement in sports. However, although previous research works in the literature address the use of motion capture systems by means of optoelectronic sensors, Inertial Measurement Units (IMUs) and depth cameras, few of them discuss their conception, guidelines and algorithms for measuring and calculating gait metrics. Moreover, commercially available motion capture systems, although efficient, are cost restrictive for most of the low-income institutions. In this research work, a new computer vision-based system (CVS) for gait analysis is developed and proposed. The aim is to close the gap found in the literature about the design and development of such systems by providing the requirements, considerations, algorithms and methodologies used to develop a gait analysis system with acceptable precision and accuracy, and at low cost. For this purpose, a linear computer vision method based on the non-homogeneous solution of the calibration matrix was used. The spatio-temporal and angular gait parameters were implemented in the proposed system, and compared with those reported in the literature. The denoising of the spatial gait trajectories and the strategies to detect gait events, are also presented and discussed. The results have shown that the proposed system is satisfactory for human gait analysis in terms of precision, computational performance and low cost. [ABSTRACT FROM AUTHOR]

• The proposed neural network-method can generate holograms significantly faster than conventional iterative algorithms, with the same or better reconstructed image quality. • Reconstruction of 3D-holograms with 16 object planes was achieved, which is the highest number of planes demonstrated using a neural network-based method to date. • A convolutional two branch neural network architecture that used one branch for generation of the phase information and one for generation of the amplitude information in the hologram reconstruction plane. • Each 2D-plane of a 3D-scene is separately propagated to the spatial light modulator (SLM) plane using such parameters as laser wavelength, SLM pixel size, and distance to the reconstruction plane, that can be independent between different planes. • Due to the integration of the propagation parameters into the training process, the network can generate holograms that can be reconstructed on random optical setups with different equipment. Computer generated holograms can create arbitrary light distributions through computation of light propagation. 3D-computer-generated-hologram generation requires significant computation time, especially so for 3D-computer-generated-holograms where it is important to calculate the interactions between different planes on top of the planes themselves. In this paper we propose a neural-network-based method for 3D-computer-generated-hologram generation in order to improve the hologram computation speed. The trained model can be used to generate holograms with arbitrary light propagation parameters. The neural network was numerically and optically tested against the GS algorithm using 3D-computer-generated-holograms with resolution up to 1024×1024 pixels. 3D-holograms with 16 object planes were generated, which is, to our knowledge, the highest number currently achieved with a neural-network-based-method. The experiments show that proposed model can create holograms significantly faster than some conventional algorithms and, overall, results better-quality images. The trained network can also be used using different propagation parameters, such as wavelength and focal distance. [ABSTRACT FROM AUTHOR]

Photometric Stereo (PS) addresses the challenge of reconstructing a three-dimensional (3D) representation of an object by estimating the 3D normals at all points on the object's surface. This is achieved through the analysis of at least three photographs, all taken from the same viewpoint but with distinct lighting conditions. This paper introduces a novel approach for Universal PS, i.e., when both the active lighting conditions and the ambient illumination are unknown. Our method employs a multi-scale encoder–decoder architecture based on Transformers that allows to accommodates images of any resolutions as well as varying number of input images. We are able to scale up to very high resolution images like 6000 pixels by 8000 pixels without losing performance and maintaining a decent memory footprint. Moreover, experiments on publicly available datasets establish that our proposed architecture improves the accuracy of the estimated normal field by a significant factor compared to state-of-the-art methods. Code and dataset available at: https://clement-hardy.github.io/Uni-MS-PS/index.html. • Universal photometric stereo for all lighting and environments. • 3D reconstruction method that scales up to very high-resolution images. • New diverse training synthetic dataset for photometric stereo. [ABSTRACT FROM AUTHOR]

Introduction: Sacral neuromodulation (SNM) is an effective treatment of urinary and bowel dysfunction, including secondary to neurological disorders. The learning curve for the optimal electrode placement for SNM is steep, expensive, and limited by patient factors such as obesity and previous injuries. We aim to create a patient specific 3‐dimensional (3D) model for successful SNM training. Materials and Methods: A total of 26 urology residents who had different level of knowledge and experience were enrolled to the 3D SNM training program. The creation of 3D sacrum model has been started with evaluation of real patient computerized tomography images and creation of Digital Imaging and Communications in Medicine files. The segmented anatomic structures from the files then edited and stereolithographic files were generated for 3D‐model prints via Mimics© software. The 3D‐printed models were used for training and evaluation of participants during the SNM intervention was performed. The evaluation of 3D SNM model training was led by one mentor who is expert on SNM. Results: On the preprinted 3D sacrum model all 26 participants were requested to perform the essential steps to complete a SNM procedure and individual procedure time was recorded. The mean and median scores were 18.8 and 19, respectively according to Likert scores (min 11 max 28). Conclusions: SNM is increasing in popularity as a treatment option with physicians and patients with refractory symptoms. Few experienced specialists exist, and more effective training methods are needed to tackle the increasing demand, and individual patient anatomy. [ABSTRACT FROM AUTHOR]

Introduction. The three-dimensional reconstruction of the renal pelvicalyceal system (PCS) is possible when performing enhanced computed tomography (CT). However, the use of a contrast agent has its limitations associated with the presence of allergy and chronic kidney disease.Purpose of the study. To describe the method of semi-autonomous three-dimensional (3D) reconstruction of the PCS based on non-enhanced CT images of patients with upper urinary tract obstruction.Materials and methods. Five patients diagnosed with renal colic were recruited from April-May 2021. All patients underwent CT-urography after informed consent. Medical Imaging Interaction Toolkit program (MITK) expanded with explainable update were used for 3D-reconstruction of PCS via excretory and native phases. To assess the accuracy of the latter, both contrast and non-contrast models were compared regarding their surface area. Also, the PCS of one patient was used to reconstruct virtual endoscopic views based on enhanced and non-enhanced models. Five urologists estimated their similarity and potential use of non-enhanced models for the interventional planning via a Likert scale questionnaire. The resulting models were also analyzed by programmer-engineers to test their suitability for 3D-printing.Results. The average surface area of enhanced and non-enhanced models was 3291 mm2 and 2879 mm2, respectively. Obtained models were suitable for their intraluminal reconstruction and potential 3D-printing. Analyzed properties of non-enhanced models were estimated at 4.5 out of 5.0.Conclusion. The described semi-autonomous reconstruction of the renal PCS based on non-enhanced CT images allows for a short time to reconstruct its 3D-view in patients with the upper urinary tract obstruction.

Abstract Background Surface roughness has a significant effect on leaf wettability. Consequently, it influences the efficiency and effectiveness of pesticide application. Therefore, roughness measurement of leaf surface offers support to the relevant research efforts. To characterize surface roughness, the prevailing methods have drawn support from large equipment that often come with high costs and poor portability, which is not suitable for field measurement. Additionally, such equipment may even suffer from inherent drawbacks like the absence of relationship between pixel intensity and corresponding height for scanning electron microscope (SEM). Results An imaging system with variable object distance was created to capture images of plant leaves, and a method based on shape from focus (SFF) was proposed. The given space-variantly blurred images were processed with the proposed algorithm to obtain the surface roughness of plant leaves. The algorithm improves the current SFF method through image alignment, focus distortion correction, and the introduction of NaN values that allows it to be applied for precise 3d-reconstruction and small-scale surface roughness measurement. Conclusion Compared with methods that rely on optical three-dimensional interference microscope, the method proposed in this paper preserves the overall topography of leaf surface, and achieves superior cost performance at the same time. It is clear from experiments on standard gauge blocks that the RMSE of step was approximately 4.44 µm. Furthermore, according to the Friedman/Nemenyi test, the focus measure operator SML was expected to demonstrate the best performance.

The fine-structural organization of the protoperidiniacean Kolkwitziella acuta was examined by SEM and TEM. Serial sections of five cells of K. acuta were used to study the architecture of basal bodies and associated roots, the pusular system, and the feeding apparatus. The basal bodies were inserted 1 µm apart at an angle of ca. 80°, and displayed the typical peridinioid features of associating with two roots each and having a layered connective linking the longitudinal microtubular root to the transverse striated root. The transverse flagellar canal was associated with a 'sac pusule', while the longitudinal flagellar canal was linked, via a pusule canal surrounded by a conspicuous layer of striated material, to a collecting chamber from which ca. 40 pusular tubes radiated. An extruded pallium was present, associated with a microtubular strand (the MSP) that extended anteriorly and progressively separated into six or seven groups of microtubules, with electron-opaque vesicles present along the MSP. A prominent striated collar surrounded the exit area of the pallium and was connected to the striated collars of both the transverse and longitudinal flagellar canals. The partial nuclear-encoded LSU rDNA sequence confirmed the identification as K. acuta. The currently known fine-structural features of pallium-feeding Protoperidiniaceae are summarized. [ABSTRACT FROM AUTHOR]

Incisional hernias occur in about 15 % of all patients that undergo abdominal surgery. Treatment of giant incisional ventral hernias (GIH) results in a surgical challenge associated with postoperative morbidities, risk of hernia recurrence, and costs. In recent years the use of both botulinum toxin (BT) to overcome abdominal cavity leakage and improved preoperative imaging studies by 3D-reconstruction has improved outcomes after these complex procedures. We describe a case of 3D-reconstruction technique before and after the use of botulinum toxin for complex ventral incisional hernia. No intraoperative complications or technical failures of the system were recorded. The operative time was 180 min, and the length of hospital stay was five days. In this preliminary study we showed our experience with the use of 3D-reconstruction of abdominal wall following preoperative BT preparation for elective surgical repair of recurrent complex incisional hernias. The use of 3D-recostruction provides important information for a correct pre-surgical planning. • The use of botulinum toxin for giant ventral hernia • The use of 3D-reconstruction technology in the abdominal wall field • News about pre-surgical planning in the abdominal wall field • Tools for elective surgical repair of complex incisional hernias [ABSTRACT FROM AUTHOR]

• 3DEM reveals dendrite diameter and spine density correlate with microtubule number. • In thick dendrites, microtubules support both dendritic branches and spines. • In thin unbranched dendrites, microtubules need only support local dendritic spines. • Existing dendritic microtubules are sufficient to supply synapses after plasticity. • Resources are delivered to and from dendrites in proportion to synapse load. Microtubules deliver essential resources to and from synapses. Three-dimensional reconstructions in rat hippocampus reveal a sampling bias regarding spine density that needs to be controlled for dendrite caliber and resource delivery based on microtubule number. The strength of this relationship varies across dendritic arbors, as illustrated for area CA1 and dentate gyrus. In both regions, proximal dendrites had more microtubules than distal dendrites. For CA1 pyramidal cells, spine density was greater on thicker than thinner dendrites in stratum radiatum , or on the more uniformly thin terminal dendrites in stratum lacunosum moleculare. In contrast, spine density was constant across the cone shaped arbor of tapering dendrites from dentate granule cells. These differences suggest that thicker dendrites supply microtubules to subsequent dendritic branches and local dendritic spines, whereas microtubules in thinner dendrites need only provide resources to local spines. Most microtubules ran parallel to dendrite length and associated with long, presumably stable mitochondria, which occasionally branched into lateral dendritic branches. Short, presumably mobile, mitochondria were tethered to microtubules that bent and appeared to direct them into a thin lateral branch. Prior work showed that dendritic segments with the same number of microtubules had elevated resources in subregions of their dendritic shafts where spine synapses had enlarged, and spine clusters had formed. Thus, additional microtubules were not required for redistribution of resources locally to growing spines or synapses. These results provide new understanding about the potential for microtubules to regulate resource delivery to and from dendritic branches and locally among dendritic spines. [ABSTRACT FROM AUTHOR]

Abstract Background Recently, the infra-acetabular screw has been proposed for use in treatment of acetabular fractures as a part of a periacetabular fixation frame. Biomechanical studies have shown that an additional infra-acetabular screw placement can enhance the fixation strength of acetabular fracture internal fixation. Currently, the reported exit point of the infra-acetabular screw has been located at the ischial tuberosity (Screw I). However, our significant experience in placement of the infra-acetabular screw has suggested that when the exit point is located between the ischial tuberosity and the ischial spine (Screw II), the placement of a 3.5 mm infra-acetabular screw may be easier for some patients. We conducted this study in order to determine the anatomical differences between the two different IACs. Methods The raw datasets were reconstructed into 3D models using the software MIMICS. Then, the models, in the STL format model, were imported into the software Geomagic Studio to delete the inner triangular patches. Additionally, the STL format image processed by Geomagic Studio was imported again into MIMICS. Finally, we used an axial perspective based on 3D models in order to study the anatomical parameters of the two infra-acetabular screw corridors with different exit points. Hence, we placed the largest diameter virtual screw in the two different screw corridors. The data obtained from this study presents the maximum diameter, length, direction, and distances between the entry point and center of IPE. Results In 65.31% males and 40.54% females, we found a screw I corridor with a diameter of at least 5 mm, while a screw II corridor was present in 77.55% in males and 62.16% in females. Compared to screw I, the length of screw II is reduced, the angle with the coronal plane is significantly reduced, and the angle with the transverse plane is significantly increased. Conclusions For East Asians, changing the exit point of the infra-acetabular screw can increase the scope of infra-acetabular screw use, especially for females.

For the gastroscopic examination of the stomach, the restricted field of view related to the „keyhole“-perspective of the endoscope is known to be a visual limitation. Thus, a panoramic extension can enlarge the field of vision, supports the endoscopist during the examination, and ensures that all of the inner stomach walls are visually inspected. To compute such a panorama of the stomach, knowledge about the geometry of the underlying structure is required. Structure from motion an approach to reconstruct the necessary information about the 3D-structure from monocular image sequences as provided by a gastroscope. We examine and evaluate an existing deep neuronal network for stereo reconstruction, in order to approximate the geometry of stomach parts from a set of consecutive acquired image pairs from gastroscopic videos.

ABSTRACT Objective: To implement one analysis method of the ankle bone contour that could make a more precise ankle arthrodesis. Methods: Twenty tomographies were submitted to 3D reconstruction. Seven points of anatomic interest for ankle arthrodesis with the three screws technique were marked with a triplannar marker. The median of the position of markers was estimated, and the union of the seven median points allow the construction of one median ankle for that population. Using this median ankle, sizes and angles for the screws position were determined. Results: Two median ankles were reconstructed, left and right. The position of the screw passage were determined considering the anatomical parameters. In the right ankle the lateral to medial screw should enter 4.56 cm and 0.79 above and posterior to lateral malleolus, with one inclination of 17.34° in relation to tibial longitudinal axis; and 0° in relation to tibial axial plane. The position for the other two screws is also described. Conclusion: Our article is the first to presents one precise guide for ankle arthrodesis based on a populational assessment. Level of evidence II, Diagnostic Studies.

Females of the solitary digger wasp tribe Philanthini, called the beewolves (Hymenoptera, Crabronidae), cultivate strains of symbiotic bacteria that belong to the genus Streptomyces in unique and highly specialized glands in their antennae. The glands consist of large reservoirs that are surrounded by numerous gland cell complexes (class III). The symbionts are cultivated inside the reservoirs and are probably provisioned with nutrients secreted from the surrounding glands and/or sequestered from the hemolymph. The wasp female delivers the bacteria into the subterranean brood cell prior to oviposition. Fully grown larvae take up the bacteria and apply them to their cocoon. There the bacteria produce several antibiotics that protect the wasp offspring against fungus infestation. Hitherto Streptomyces bacteria were detected in the antennae of 38 species of the Philanthini. However, a detailed morphological analysis of the antennal glands is only available for a few species. In order to shed light on the evolutionary history of the association between beewolf wasps and bacteria, we investigated the morphology of the antennal glands of another 14 Philanthus species from the Palearctic, Paleotropic, and Nearctic. We generated 3D-models of the glands based on serial semithin sections and/or micro-CT (μCT). Despite broad similarities in number and structure of antennal glands, the results revealed interspecific differences with regard to overall shape, complexity, and relative size of the reservoirs as well as the number of the surrounding gland cell units. Mapping the morphology of all species studied so far on the phylogeny (that parallels geographical distribution) revealed that related species share similarities in gland morphology, but there are notable differences between lineages. In particular, compared to the North American species the European and African species possess more complex gland structures with a higher number of gland cells. We discuss morphological, ecological, and physiological aspects and provide scenarios for the evolution of the antennal glands of the Philanthini as symbiont cultivation organs.

Females of the solitary digger wasp tribe Philanthini , called the beewolves (Hymenoptera, Crabronidae), cultivate strains of symbiotic bacteria that belong to the genus Streptomyces in unique and highly specialized glands in their antennae. The glands consist of large reservoirs that are surrounded by numerous gland cell complexes (class III). The symbionts are cultivated inside the reservoirs and are probably provisioned with nutrients secreted from the surrounding glands and/or sequestered from the hemolymph. The wasp female delivers the bacteria into the subterranean brood cell prior to oviposition. Fully grown larvae take up the bacteria and apply them to their cocoon. There the bacteria produce several antibiotics that protect the wasp offspring against fungus infestation. Hitherto Streptomyces bacteria were detected in the antennae of 38 species of the Philanthini. However, a detailed morphological analysis of the antennal glands is only available for a few species. In order to shed light on the evolutionary history of the association between beewolf wasps and bacteria, we investigated the morphology of the antennal glands of another 14 Philanthus species from the Palearctic, Paleotropic, and Nearctic. We generated 3D-models of the glands based on serial semithin sections and/or micro-CT (μCT). Despite broad similarities in number and structure of antennal glands, the results revealed interspecific differences with regard to overall shape, complexity, and relative size of the reservoirs as well as the number of the surrounding gland cell units. Mapping the morphology of all species studied so far on the phylogeny (that parallels geographical distribution) revealed that related species share similarities in gland morphology, but there are notable differences between lineages. In particular, compared to the North American species the European and African species possess more complex gland structures with a higher number of gland cells. We discuss morphological, ecological, and physiological aspects and provide scenarios for the evolution of the antennal glands of the Philanthini as symbiont cultivation organs. [ABSTRACT FROM AUTHOR]

The methods employed to document cystoscopic findings in bladder cancer patients lack accuracy and are subject to observer variability. We propose a novel endoimaging system and an online documentation platform to provide post-procedural 3D bladder reconstructions for improved diagnosis, management and follow-up. The RaVeNNA4pi consortium is comprised of five industrial partners, two university hospitals and two technical institutes. These are grouped into hardware, software and clinical partners according to their professional expertise. The envisaged endoimaging system consists of an innovative cystoscope that generates 3D bladder reconstructions allowing users to remotely access a cloud-based centralized database to visualize individualized 3D bladder models from previous cystoscopies archived in DICOM format. Preliminary investigations successfully tracked the endoscope's rotational and translational movements. The structure-from-motion pipeline was tested in a bladder phantom and satisfactorily demonstrated 3D reconstructions of the processing sequence. AI-based semantic image segmentation achieved a 0.67 dice-score-coefficient over all classes. An online-platform allows physicians and patients to digitally visualize endoscopic findings by navigating a 3D bladder model. Our work demonstrates the current developments of a novel endoimaging system equipped with the potential to generate 3D bladder reconstructions from cystoscopy videos and AI-assisted automated detection of bladder tumors. [ABSTRACT FROM AUTHOR]

Nudibranchia is a group of shell-less heterobranch gastropods characterized by highly specialized chemosensory cephalic organs known as rhinophores. Whereas the morphology of the rhinophore is an important taxonomic character, as the external structures are used when describing species. However, the internal morphology of the rhinophore has only been studied in terms of neurophysiology. In this study, for the first time, the external and internal structure of the rhinophore in Onchidoris muricata (O.F. Müller, 1776) is described in detail using methods of light, scanning electron-, transmission electron- and confocal laser scanning microscopy, as well as computer microtomography (micro-CT). Data obtained showed that spicules of the rhinophore significantly differ from the body spicules in both general morphology and localization. The thinner and longer spicules of the rhinophore form the spiral square mesh network, allowing mobility which permits contraction of the rhinophore while maintaining a strong framework. Interestingly, the ultrathin structure of the spicules and scleroblasts resemble those of the body spicules. The lymphatic canal and the large nerve and associated longitudinal muscles are situated in the central part of the rhinophore. Stemming from the large nerve are thin transverse muscles and nerve branches associated with the rhinophore lamellae. Morphological analyses suggest a lymphatically driven mechanism in O. muricata, which is capable of quick muscular contraction and slow retraction of the rhinophore. • Rhinophores in Onchidoris muricata (O. F. Müller, 1776) are fortified by unique spicules • Rhinophore spicule morphology and co-location differ from body spicules • The spicules form the mobile network like spiral square mesh • Rhinophore retraction occurs in two phases by two retractor muscle groups • Relaxation of the rhinophore occurs passively due to injection of hemolymph [ABSTRACT FROM AUTHOR]

Small-conductance calcium-activated potassium (SK) channels are crucial for learning and memory. However, many aspects of their spatial organization in neurons are still unknown. In this study, we have taken a novel approach to answering these questions combining a pre-embedding immunogold labeling with an automated dual-beam electron microscope that integrates focused ion beam milling and scanning electron microscopy (FIB/SEM) to gather 3D map ultrastructural and biomolecular information simultaneously. Using this new approach, we evaluated the number and variability in the density of extrasynaptic SK2 channels in 3D reconstructions from six dendritic segments of excitatory neurons and six inhibitory neurons present in the stratum radiatum of the CA1 region of the mouse. SK2 immunoparticles were observed throughout the surface of hippocampal neurons, either scattered or clustered, as well as at intracellular sites. Quantitative volumetric evaluations revealed that the extrasynaptic SK2 channel density in spines was seven times higher than in dendritic shafts and thirty-five times higher than in interneurons. Spines showed a heterogeneous population of SK2 expression, some spines having a high SK2 content, others having a low content and others lacking SK2 channels. SK2 immunonegative spines were significantly smaller than those immunopositive. These results show that SK2 channel density differs between excitatory and inhibitory neurons and demonstrates a large variability in the density of SK2 channels in spines. Furthermore, we demonstrated that SK2 expression was associated with excitatory synapses, but not with inhibitory synapses in CA1 pyramidal cells. Consequently, regulation of excitability and synaptic plasticity by SK2 channels is expected to be neuron class- and target-specific. These data show that immunogold FIB/SEM represent a new powerful EM tool to correlate structure and function of ion channels with nanoscale resolution. [ABSTRACT FROM AUTHOR]

Microscopic organisms that penetrate calcareous structures by actively dissolving the carbonate matrix, namely microendoliths, have an important influence on the breakdown of marine carbonates. The study of these microorganisms and the bioerosion traces they produce is crucial for understanding the impact of their bioeroding activity on the carbonate recycling in environments under global climate change. Traditionally, either the extracted microendoliths were studied by conventional microscopy or their traces were investigated using scanning electron microscopy (SEM) of epoxy resin casts. A visualisation of the microendoliths in situ, that is within their complex microbioerosion structures, was previously limited to the laborious and time‐consuming double‐inclusion cast‐embedding technique. Here, we assess the applicability of various fluorescence staining methods in combination with confocal laser scanning microscopy (CLSM) for the study of fungal microendoliths in situ in partly translucent mollusc shells. Among the tested methods, specific staining with dyes against the DNA (nuclei) of the trace making organisms turned out to be a useful and reproducible approach. Bright and clearly delineated fluorescence signals of microendolithic nuclei allow, for instance, a differentiation between abandoned and still populated microborings. Furthermore, infiltrating the microborings with fluorescently stained resin seems to be of great capability for the visualisation and quantification of microbioerosion structures in their original spatial orientation. Potential fields of application are rapid assessments of endolithic bio‐ and ichnodiversity and the quantification of the impact of microendoliths on the overall calcium carbonate turnover. The method can be applied after CLSM of the stained microendoliths and retains the opportunity for a subsequent investigation of epoxy casts with SEM. This allows a three‐fold approach in studying microendoliths in the context of their microborings, thereby fostering the integration of biological and ichnological aspects of microbial bioerosion. [ABSTRACT FROM AUTHOR]

Small-conductance calcium-activated potassium (SK) channels are crucial for learning and memory. However, many aspects of their spatial organization in neurons are still unknown. In this study, we have taken a novel approach to answering these questions combining a pre-embedding immunogold labeling with an automated dual-beam electron microscope that integrates focused ion beam milling and scanning electron microscopy (FIB/SEM) to gather 3D map ultrastructural and biomolecular information simultaneously. Using this new approach, we evaluated the number and variability in the density of extrasynaptic SK2 channels in 3D reconstructions from six dendritic segments of excitatory neurons and six inhibitory neurons present in the stratum radiatum of the CA1 region of the mouse. SK2 immunoparticles were observed throughout the surface of hippocampal neurons, either scattered or clustered, as well as at intracellular sites. Quantitative volumetric evaluations revealed that the extrasynaptic SK2 channel density in spines was seven times higher than in dendritic shafts and thirty-five times higher than in interneurons. Spines showed a heterogeneous population of SK2 expression, some spines having a high SK2 content, others having a low content and others lacking SK2 channels. SK2 immunonegative spines were significantly smaller than those immunopositive. These results show that SK2 channel density differs between excitatory and inhibitory neurons and demonstrates a large variability in the density of SK2 channels in spines. Furthermore, we demonstrated that SK2 expression was associated with excitatory synapses, but not with inhibitory synapses in CA1 pyramidal cells. Consequently, regulation of excitability and synaptic plasticity by SK2 channels is expected to be neuron class- and target-specific. These data show that immunogold FIB/SEM represent a new powerful EM tool to correlate structure and function of ion channels with nanoscale resolution.

Chromatic aberrations are mostly supressed in typical industrial lenses to ensure a well-defined colour image. Beside the main wavelengths which are recognizable for the human eye, multispectral cameras can sample with a more detailed chromatic (spectral) resolution. This leads to a partial wavelength depended unsharpness in the images. If the imaging system can be well defined out of these imperfections, a depth information can be calculated. In this paper the theoretical model as well as a method for the 3D-reconstruction out of different colour (spectral) channels will be discussed.

In this work, we present a new versatile 3D multilinear statistical face model, based on a tensor factorisation of 3D face scans, that decomposes the shapes into person and expression subspaces. Investigation of the expression subspace reveals an inherent low-dimensional substructure, and further, a star-shaped structure. This is due to two novel findings. (1) Increasing the strength of one emotion approximately forms a linear trajectory in the subspace. (2) All these trajectories intersect at a single point – not at the neutral expression as assumed by almost all prior works—but at an apathetic expression. We utilise these structural findings by reparameterising the expression subspace by the fourth-order moment tensor centred at the point of apathy. We propose a 3D face reconstruction method from single or multiple 2D projections by assuming an uncalibrated projective camera model. The non-linearity caused by the perspective projection can be neatly included into the model. The proposed algorithm separates person and expression subspaces convincingly, and enables flexible, natural modelling of expressions for a wide variety of human faces. Applying the method on independent faces showed that morphing between different persons and expressions can be performed without strong deformations. [ABSTRACT FROM AUTHOR]

Background: Surface roughness has a significant effect on leaf wettability. Consequently, it influences the efficiency and effectiveness of pesticide application. Therefore, roughness measurement of leaf surface offers support to the relevant research efforts. To characterize surface roughness, the prevailing methods have drawn support from large equipment that often come with high costs and poor portability, which is not suitable for field measurement. Additionally, such equipment may even suffer from inherent drawbacks like the absence of relationship between pixel intensity and corresponding height for scanning electron microscope (SEM). Results: An imaging system with variable object distance was created to capture images of plant leaves, and a method based on shape from focus (SFF) was proposed. The given space-variantly blurred images were processed with the proposed algorithm to obtain the surface roughness of plant leaves. The algorithm improves the current SFF method through image alignment, focus distortion correction, and the introduction of NaN values that allows it to be applied for precise 3d-reconstruction and small-scale surface roughness measurement. Conclusion: Compared with methods that rely on optical three-dimensional interference microscope, the method proposed in this paper preserves the overall topography of leaf surface, and achieves superior cost performance at the same time. It is clear from experiments on standard gauge blocks that the RMSE of step was approximately 4.44 µm. Furthermore, according to the Friedman/Nemenyi test, the focus measure operator SML was expected to demonstrate the best performance. [ABSTRACT FROM AUTHOR]

The image quality might be degraded severely due to water scatterings, especially near-shore water scatterings. In addition, the degraded image reduces the accuracy of underwater 3D reconstruction. We propose an underwater imaging system based on light field camera array to obtain enhanced high-quality images and accurate three-dimensional reconstruction from harsh underwater environments. Both 2D-imaging and 3D-reconstruction using light-field imaging were studied by experiments. By refocusing and analyzing the light field images of the target through turbid water, we obtained accurate three-dimensional estimations in the underwater scene. These experiments confirm the reliability of our method, showing that the SSIM (structural similarity) value of the system in turbid water is 0.378, compared to 0.197, the SSIM value of conventional single-camera imaging in the experiments. Therefore, we verify that the light field imaging system is less affected by forward scattering of water and has a larger detective range than conventional single-camera imaging with any specific resolution. [ABSTRACT FROM AUTHOR]

Objective: This study compared our program's ("InsKid") capability for measuring the infundibulopelvic angle (IPA) with existing ones. Methods: Prospectively, data from 50 patients with lower pole kidney stones with indications for retrograde intrarenal surgery (RIRS) were collected. All patients underwent computed tomography (CT)-urography. The IPA of each pelvicalyceal (PCS) unit was measured with the Elbahnasy's, Sampaio's, and "InsKid" methods. Results were compared. Finally, we compared the area under the receiver operating characteristic (ROC) curve (AUC) for predicting stone-free status after RIRS. We defined success as stone fragments ≤ 2 mm on the CT scan on the first postoperative day (POD1). The stone-free rate refers to no identifiable stone fragments on the POD1 CT. Test–retest reliability and face validity were defined to estimate psychometric properties of InsKid. Results: The success rate after first procedure was 87.5%. The average value of IPA using the Elbahnasy and Sampaio methods and our program were 85.2° ± 11.9°, 95.1° ± 10.1°, and 79.9° ± 13.0, respectively. There was a significant difference among the InsKid, Elbahnasy, and Sampaio (AUC = 0.762, 0.601, and 0.629, respectively) approaches with respect to the capability of predicting the immediate success of RIRS. Repeated measurement did not affect values of IPA (1.3° ± 0.7, p = 0.67). All specialist appreciated proposed software as highly useful (5/5). Conclusion: This new application reproduces the intraoperative aspects of the PCS more clearly than the other methods and also provides an easy solution for clearly defining the IPA without relying on the central axes. [ABSTRACT FROM AUTHOR]

The Southern house mosquito Culex quinquefasciatus relies on its olfactory system to locate the human hosts for blood meals, by which several deadly diseases are transmitted. Olfactory sensory neurons (OSNs) housed in the sensilla on the olfactory appendages send their axons into the antennal lobes (ALs), the primary olfactory center in the brain, where the OSNs expressing the same olfactory receptors converge upon the same spherical structures known as glomeruli in the AL. The structure of the antennal lobe, that is, the spatial organization of the glomeruli, governs the insect's odor identification and discrimination. Drosophila studies have demonstrated the specific connections between receptors and glomeruli based on the 3D structure of the antennal lobe, deepening our understanding of the relationships between glomerular activities and behaviors, but as yet the structure of the Cx. quinquefasciatus antennal lobe remains unknown. We therefore constructed a 3D model of the Cx. quinquefasciatus antennal lobe using nc82 antibody staining, identifying 62 and 44 glomeruli in the female and male mosquito antennal lobe, respectively, with a significant sexual dimorphism in terms of the antennal lobe volume and glomerulus number. These results demonstrate the structural basis of mosquito odor coding and provide a platform for future studies of the mosquito olfactory signal processing mechanism. [ABSTRACT FROM AUTHOR]

This data article presents datasets associated with the research article entitled “The immunological architecture of granulomatous inflammation in central nervous system tuberculosis’’ (Zaharie et al., 2020). The morphology of tuberculosis related granulomas within the central nervous system of human patients was visualized in six different three-dimensional (3D) models. Post-mortem, formalin fixed and paraffin embedded specimens from deceased tuberculous meningitis patients were immunohistochemically stained and 800 serial histologically stained sections were acquired. Images from all sections were obtained with an Olympus BX43 light microscope and structures were identified, labeled and made three-dimensional. The interactive 3D-models allows the user to directly visualize the morphology of the granulomas and to understand the localization of the granulomas. The 3D-models can be used for multiple purposes and provide both an educational source as a gold standard for further animal studies, human research and the development of in silico models on the topic of central nervous system tuberculosis.

Background: Recently, the infra-acetabular screw has been proposed for use in treatment of acetabular fractures as a part of a periacetabular fixation frame. Biomechanical studies have shown that an additional infra-acetabular screw placement can enhance the fixation strength of acetabular fracture internal fixation. Currently, the reported exit point of the infra-acetabular screw has been located at the ischial tuberosity (Screw I). However, our significant experience in placement of the infra-acetabular screw has suggested that when the exit point is located between the ischial tuberosity and the ischial spine (Screw II), the placement of a 3.5 mm infra-acetabular screw may be easier for some patients. We conducted this study in order to determine the anatomical differences between the two different IACs.Methods: The raw datasets were reconstructed into 3D models using the software MIMICS. Then, the models, in the STL format model, were imported into the software Geomagic Studio to delete the inner triangular patches. Additionally, the STL format image processed by Geomagic Studio was imported again into MIMICS. Finally, we used an axial perspective based on 3D models in order to study the anatomical parameters of the two infra-acetabular screw corridors with different exit points. Hence, we placed the largest diameter virtual screw in the two different screw corridors. The data obtained from this study presents the maximum diameter, length, direction, and distances between the entry point and center of IPE.Results: In 65.31% males and 40.54% females, we found a screw I corridor with a diameter of at least 5 mm, while a screw II corridor was present in 77.55% in males and 62.16% in females. Compared to screw I, the length of screw II is reduced, the angle with the coronal plane is significantly reduced, and the angle with the transverse plane is significantly increased.Conclusions: For East Asians, changing the exit point of the infra-acetabular screw can increase the scope of infra-acetabular screw use, especially for females. [ABSTRACT FROM AUTHOR]

Sound-producing organs generate acoustic signals that have a fundamental role in communication systems. In species exhibiting different biogeographic patterns, variations of these structures can explain a large part of interpopulation differences of their signals. Pleurodema thaul is an anuran with an extensive geographic distribution in Chile and presents an evident divergence in its acoustic signals among three genetic/bioacoustic groups (i.e. northern, central and southern). By means of classic histology and 3D-reconstructions, we study the geographic variation in the larynx of P. thaul males from these three groups. In addition, volumes of six laryngeal structures are used as predictors of acoustic characteristics of advertisement calls recorded in previous studies for the same subjects used in the current study. After removing the effect of body size, the arytenoid cartilage, dilator muscle and vocal cords show significant differences between the three bioacoustic groups. Furthermore, arytenoid cartilage and dilator muscle volumes predict some temporal parameters and also the dominant frequency of advertisement calls. Our results show important geographic variation in laryngeal morphology, which is in correspondence with acoustic, behavioural and genetic variation in this species. [ABSTRACT FROM AUTHOR]

All microsporidia share a unique, extracellular spore stage, containing the infective sporoplasm and the apparatus for initiating infection. The polar filament/polar tube when exiting the spore transports the sporoplasm through it into a host cell. While universal, these structures and processes have been enigmatic. This study utilized several types of microscopy, describing and extending our understanding of these structures and their functions. Cryogenically preserved polar tubes vary in diameter from 155 to over 200 nm, noticeably larger than fixed‐sectioned or negatively stained samples. The polar tube surface is pleated and covered with fine fibrillar material that projects from the surface and is organized in clusters or tufts. These fibrils may be the sites of glycoproteins providing protection and aiding infectivity. The polar tube surface is ridged with 5–6 nm spacing between ridges, enabling the polar tube to rapidly increase its diameter to facilitate the passage of the various cargo including cylinders, sacs or vesicles filled with particulate material and the intact sporoplasm containing a diplokaryon. The lumen of the tube is lined with a membrane that facilitates this passage. Careful examination of the terminus of the tube indicates that it has a closed tip where the membranes for the terminal sac are located. [ABSTRACT FROM AUTHOR]

Mygalomorphs are a well-known spider group; however, astonishingly little is known about their internal anatomy. As part of a comparative survey on the circulatory system in spiders, we conducted an examination of the hemolymph vascular system (HVS) and parts of the hemolymph lacunar system (HLS) in five mygalomorph spider species. Circulatory system features were investigated using micro-computer-tomography in combination with resin injection methods and serial sectioning. Data were visualized using a 3D-reconstruction software. The HVS consists of a tubular heart, which is situated along the dorsal midline of the opisthosoma. Anteriorly, the heart gives rise to the anterior aorta. A posterior aorta system was not found. Three pairs of cardiac arteries originate laterally from the heart and the branching pattern of these arteries is visualized and described here for the first time. The anterior aorta runs through the pedicel into the prosoma where it branches to supply the muscles and particularly the central nervous system. The data on mygalomorphs are discussed in comparison to the HVS in other Araneae. [ABSTRACT FROM AUTHOR]

Like all skeletal muscles, the diaphragm muscle accomplishes a range of motor behaviors by recruiting different motor unit types in an orderly fashion. Recruitment of phrenic motor neurons (PhMNs) is generally assumed to be based primarily on the intrinsic properties of PhMNs with an equal distribution of descending excitatory inputs to all PhMNs. However, differences in presynaptic excitatory input across PhMNs of varying sizes could also contribute to the orderly recruitment pattern. In the spinal cord of Sprague-Dawley rats, we retrogradely labeled PhMNs using cholera toxin B (CTB) and validated a robust confocal imaging-based technique that utilizes semiautomated processing to identify presynaptic glutamatergic (Glu) terminals within a defined distance around the somal membrane of PhMNs of varying size. Our results revealed an ~10% higher density of Glu terminals at PhMNs in the lower tertile of somal surface area. These smaller PhMNs are likely recruited first to accomplish lower force ventilatory behaviors of the diaphragm as compared with larger PhMNs in the upper tertile that are recruited to accomplish higher force expulsive behaviors. These results suggest that differences in excitatory synaptic input to PhMNs may also contribute to the orderly recruitment of diaphragm motor units. [ABSTRACT FROM AUTHOR]

We propose a camera model for cameras with hypercentric lenses. Because of their geometry, hypercentric lenses allow to image the top and the sides of an object simultaneously. This makes them useful for certain inspections tasks, for which otherwise multiple images would have to be acquired and stitched together. After describing the projection geometry of hypercentric lenses, we derive a camera model for hypercentric lenses that is intuitive for the user. Furthermore, we describe how to determine the parameter values of the model by calibrating the camera with a planar calibration object. We also apply our camera model to two example applications: in the first application, we show how two cameras with hypercentric lenses can be used for dense 3D reconstruction. For an efficient reconstruction, the images are rectified such that corresponding points occur in the same image row. Standard rectification methods would result in perspective distortions in the images that would prevent stereo matching algorithms from robustly establishing correspondences. Therefore, we propose a new rectification method for objects that are approximately cylindrical in shape, which enables a robust and efficient reconstruction. In the second application, we show how to unwrap cylindrical objects to simplify further inspection tasks. For the unwrapping, the pose of the cylinder must be known. We show how to determine the pose of the cylinder based on a single camera image and based on two images of a stereo camera setup. [ABSTRACT FROM AUTHOR]

Abstract Despite the ecological significance of ants and the intensive research attention they have received, thorough treatments of the anatomy and functional morphology are still scarce. In this study we document the head morphology of workers of the myrmicine Wasmannia affinis with optical microscopy, μ-computed tomography, scanning electron microscopy, and 3D reconstruction, providing the first complete anatomical treatment of an ant head with a broad array of modern techniques. We discuss the potential of the applied methods to generate detailed and well-documented morphological data sets with increased efficiency. We also address homology problems, particularly in the context of the cephalic digestive tract. According to our analyses the "pharynx" of previous ant studies is homologous to the prepharynx of other insects. We also discuss the phylogenetic potential and functional significance of the observed characters, with internal features such as tentorium and musculature discussed for the first time. Our investigation underlines that detailed anatomical data for Formicidae are still very fragmentary, which in turn limits our understanding of the major design elements underlying the ant bauplan. We attempt to provide a template for further anatomical studies, which will help to understand the evolution of this fascinating group on the phenotypic level. Highlights • First modern documentation of the head anatomy of an ant worker. • Homology problems solved, particularly of the cephalic digestive tract. • Optimized workflow for acquisition and documentation of anatomical data. • Template for future work on ant cephalic anatomy. [ABSTRACT FROM AUTHOR]

• A novel wheat seed phenotyping platform named Seedscreener was fabricated. • Both spectrum and three-dimensional model of individual seeds are captured. • 3D morphological features of seed kernels are automatically extracted. • Machine learning can determine the multiple nutrient contents of single seed. • With high accuracy and throughput, it has potential of commercialization. Crop seed phenomics provides a new operational basis for breeders. However, a scarcity of seed phenotypic characterization, especially of the single seed kernels, severely restricts their use in plant breeding. In this study, we focus on designing and deploying a prototype for automatic and high throughput seed phenotyping. The novel setup, Seedscreener, allows simultaneous RGB imaging and NIR spectrum analysis pipeline to evaluate single kernel 3D morphologies and internal biochemicals. With the assistance of a data acquisition device centered on a near-infrared spectrometer and an industrial camera, as well as an automated acquisition software under the QT development framework, Seedscreener has the ability to acquire both endophenotype and exophenotype traits of single wheat kernels simultaneously. The developed biochemical endophenotype traits prediction model can forecast the protein content (PC), starch content (SC) and gluten content (GC) of wheat kernel by the full-band absorbance spectra. The developed morphological exophenotype traits extraction model based on Marching Cubes (MC) algorithm can calculate the wheat grain length (GL), grain width (GW), grain thickness (GT), grain surface area (GSA) and convex hull volume (CHV) using the three-dimensional visual hull constructed by the lateral profile information of the wheat grain. The results show that the platform could reach 94% success rate of single wheat phenotypic data collection, the average accuracy of endophenotype traits prediction is 0.85, the average accuracy of exophenotype traits extraction is 0.93, and the working flux of the platform is about 90 grains/h. Compared with existing individual wheat kernels phenotyping equipment, Seedscreener could obtain both endophenotype and exophenotype characteristics of wheat seeds with high throughput and precision. [ABSTRACT FROM AUTHOR]

Abstract—The effects of sensory stimulation on the model of paired Mauthner neurons of monocularly deprived goldfish have been studied by light- and electron microscopy. Three-dimensional reconstruction was performed using serial semi-thin sections in order to determine the volumes of soma and dendrites for the right and left Mauthner neurons. These data suggested that long-term stimulation of some fish caused a decrease in the volume of the lateral dendrites of neurons contralateral with respect to the side of the enucleated eye. As a result, the morphological homeostasis in the dendrites of Mauthner neurons, which was observed in the control fish, was disturbed after the effect of stimulation upon this group of fish. The main mechanism of this effect of stimulation, according to ultrastructural analysis, is the compaction of the cytoskeleton in the lateral dendrite of a neuron and a reduction in the number of synaptic vesicles in the region of afferent synapses. In contrast, stimulation of the remaining fish induced the resistance of the contralateral Mauthner neuron to prolonged stimulation, as well as the hypertrophy of its lateral and shortening of the ventral dendrites. These results suggest that the homeostasis of the dendrites of Mauthner neurons essentially depends on the state of the visual inputs, the load on which increased as a result of the doubled impact. [ABSTRACT FROM AUTHOR]

Research has shown that a large proportion of hazards remain unrecognized, which expose construction workers to unanticipated safety risks. Recent studies have also found that a strong correlation exists between viewing patterns of workers, captured using eye-tracking devices, and their hazard recognition performance. Therefore, it is important to analyze the viewing patterns of workers to gain a better understanding of their hazard recognition performance. From the training standpoint, scan paths and attention maps, generated using eye-tracking technology, can be used effectively to provide personalized and focused feedback to workers. Such feedback is used to communicate the search process deficiency to workers in order to trigger self-reflection and subsequently improve their hazard recognition performance. This paper proposes a computer vision-based method that tracks workers on a construction site and automatically locates their fixation points, collected using a wearable eye-tracker, on a 3D point cloud. This data is then used to analyze their viewing behavior and compute their attention distribution. The presented case studies validate the proposed method. [ABSTRACT FROM AUTHOR]

The need for an efficient method of integration of a dense normal field is inspired by several computer vision tasks, such as shape-from-shading, photometric stereo, deflectometry. Inspired by edge-preserving methods from image processing, we study in this paper several variational approaches for normal integration, with a focus on non-rectangular domains, free boundary and depth discontinuities. We first introduce a new discretization for quadratic integration, which is designed to ensure both fast recovery and the ability to handle non-rectangular domains with a free boundary. Yet, with this solver, discontinuous surfaces can be handled only if the scene is first segmented into pieces without discontinuity. Hence, we then discuss several discontinuity-preserving strategies. Those inspired, respectively, by the Mumford-Shah segmentation method and by anisotropic diffusion, are shown to be the most effective for recovering discontinuities. [ABSTRACT FROM AUTHOR]

The need for efficient normal integration methods is driven by several computer vision tasks such as shape-from-shading, photometric stereo, deflectometry. In the first part of this survey, we select the most important properties that one may expect from a normal integration method, based on a thorough study of two pioneering works by Horn and rooks (Comput Vis Graph Image Process 33(2): 174-208, 1986) and Frankot and Chellappa (IEEE Trans Pattern Anal Mach Intell 10(4): 439-451, 1988). Apart from accuracy, an integration method should at least be fast and robust to a noisy normal field. In addition, it should be able to handle several types of boundary condition, including the case of a free boundary and a reconstruction domain of any shape, i.e., which is not necessarily rectangular. It is also much appreciated that a minimum number of parameters have to be tuned, or even no parameter at all. Finally, it should preserve the depth discontinuities. In the second part of this survey, we review most of the existing methods in view of this analysis and conclude that none of them satisfies all of the required properties. This work is complemented by a companion paper entitled Variational Methods for Normal Integration, in which we focus on the problem of normal integration in the presence of depth discontinuities, a problem which occurs as soon as there are occlusions. [ABSTRACT FROM AUTHOR]

The presence of a swinging tentorium is a key apomorphy of Myriapoda, but this character has been studied in detail in only few species. Here the tentorium, i.e., the peristomatic skeleton of the preoral chamber, is comparatively studied in three species of the millipede order Sphaerotheriida Brandt, 1833. Since dissections of the fragile tentorial components proved to be difficult, despite the large head size, they were analysed mainly in situ via micro-computed tomography. Our results confirm previous observations of large differences in the tentorial construction in the giant pill-millipedes compared to chilognathan diplopods. The tentorium of Sphaerotheriida consists of a curved, plate-like epipharyngeal bar with distal projections, an elongate and thin hypopharyngeal bar, and a plate-like triangular posterior process; a transverse bar is absent. Only seven muscles attach at the tentorium in giant pill-millipedes, including two antennal muscles and two muscles of the gnathochilarium. Within the order Sphaerotheriida, the composition of the tentorium and its muscular equipment seems to be conserved, except for some variability in the shape of the epipharyngeal bar. As the transverse bar has been considered essential for the mobility of the tentorium in myriapods, its absence in Sphaerotheriida may indicate that their tentorium is not capable of performing a swing. Loss of tentorial mobility may also pertain to the order Glomerida Brandt, 1833, inferred here from the absence of a posterior process. An apparently immobile tentorium in Glomerida and Sphaerotheriida can straightforwardly be correlated with transformations of the head related to their ability of volvation. The different transformations of the tentorium, here hypothesised to cause immobility, may support current assumptions that the ability of volvation evolved convergently in Glomerida and Sphaerotheriida. This conclusion, however, still requires more detailed studies of the head anatomy in Glomerida and Glomeridesmida Cook, 1895. [ABSTRACT FROM AUTHOR]

Virtually no information on the chronology of prenatal development of the human urinary tract and the sex-related differences in the emergence of urinary tract topography during embryonic development is presently available. The aim of our work was to study sex-related differences in urethra development in human embryos and early fetuses. Forty-nine preparations of human embryos and early fetuses without external signs of anatomical abnormalities were studied in order to achieve the aim and fulfill the objectives of the study. Embryos and early fetuses were divided into six groups according to gestational age and parietococcygeal length. The complex of adequate methods of morphological research used in the study included preparation and microscopy of serial histological and anatomical sections of human embryos, including female and male urinary tracts, preparation of 3D-reconstruction models, and morphometry. The formation of prostatic urethra, a derivative of the urogenital sinus, was shown to occur at the beginning of the ninth week of embryogenesis, and the primordium of the internal sphincter of the urinary tract was formed at the end of the tenth week. Formation of the terminal part of spongy urethra took place during weeks 10-11 and involved funnel-like protrusion of the ectoderm from the top of the balanus towards the urethra lumen. The secondary ventral displacement of the urethral opening does not occur in female fetuses, and, therefore, only the prostatic urethra is a homolog of the female urinary tract. The pelvic part of the urogenital sinus was transformed into the prostatic urethra and the membranous urethra of the male at the end of the first stage of fetal development. Elongation of the genital tubercle (a penis primordium) and formation of the urethral ridge walls that involved the urogenital folds occurred at the same time. [ABSTRACT FROM AUTHOR]