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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.

This document presents the analysis performed over the Map Challenge dataset using a new algorithm which we refer to as Pair Comparison Method. The new algorithm, which is described in detail in the text, is able to sort reconstructions based on a figure of merit and assigns a level of significance to the sorting. That is, it shows how likely the sorting is due to chance or if it reflects real differences., Spanish Ministry of Economy and Competitiveness (BIO2013-44647-R, BIO2016-76400-R. AEI/FEDER, UE) and (AEI/FEDER BFU 2016 74868P), Comunidad Autónoma de Madrid (S2017/BMD-3817), European Union (EU) (INFRADEV-1-2014-1, Proposal: 654248)

This paper addresses the problem of simultaneously recovering 3D shape, pose and the elastic model of a deformable object from only 2D point tracks in a monocular video. This is a severely under-constrained problem that has been typically addressed by enforcing the shape or the point trajectories to lie on low-rank dimensional spaces. We show that formulating the problem in terms of a low-rank force space that induces the deformation and introducing the elastic model as an additional unknown, allows for a better physical interpretation of the resulting priors and a more accurate representation of the actual object's behavior. In order to simultaneously estimate force, pose, and the elastic model of the object we use an expectation maximization strategy, where each of these parameters are successively learned by partial M-steps. Once the elastic model is learned, it can be transfered to similar objects to code its 3D deformation. Moreover, our approach can robustly deal with missing data, and encode both rigid and non-rigid points under the same formalism. We thoroughly validate the approach on Mocap and real sequences, showing more accurate 3D reconstructions than state-of-the-art, and additionally providing an estimate of the full elastic model with no a priori information., This work has been partially supported by the Spanish Ministry of Science and Innovation under project RobInstruct TIN2014-58178-R; and by a Google Faculty Award. This work is also supported by the Spanish State Research Agency through the María de Maeztu Seal of Excellence to IRI MDM-2016-0656.

Crop monitoring is an essential practice within the field of precision agriculture since it is based on observing, measuring and properly responding to inter-and intra-field variability. In particular, “on ground crop inspection” potentially allows early detection of certain crop problems or precision treatment to be carried out simultaneously with pest detection. “On ground monitoring” is also of great interest for woody crops. This paper explores the development of a low-cost crop monitoring system that can automatically create accurate 3D models (clouds of coloured points) of woody crop rows. The system consists of a mobile platform that allows the easy acquisition of information in the field at an average speed of 3 km/h. The platform, among others, integrates an RGB-D sensor that provides RGB information as well as an array with the distances to the objects closest to the sensor. The RGB-D information plus the geographical positions of relevant points, such as the starting and the ending points of the row, allow the generation of a 3D reconstruction of a woody crop row in which all the points of the cloud have a geographical location as well as the RGB colour values. The proposed approach for the automatic 3D reconstruction is not limited by the size of the sampled space and includes a method for the removal of the drift that appears in the reconstruction of large crop rows., The Spanish Government has provided full and continuing support for this research work through project AGL2014-52465-C4-3-R. The authors wish to thank the Codorniu S.A. company for the use of the facilities on the estate of Raimat and extend their gratitude to Jordi Recasens and his team (Weed Science and Plant Ecology Research Group of the UdL) for their invaluable help in the field trials. Karla Cantuña thanks the service commission for the remuneration given by the Cotopaxi Technical University. The authors also wish to acknowledge the ongoing technical support of Damián Rodríguez

Organogenesis is a complex coordinated process of cell proliferation, growth, migration, and apoptosis. Differential growth rates, particularly during cardiogenesis, play a role in establishing morphology. Studies using stereological and cell sorting methods derive averages of morphogenetic parameters for an organ. To understand tissue composition and differential growth, the researcher must determine a number of morphogenetic parameters in the developing organ. Such measurements require sectioning to enable identification of organ borders, tissue components and cell types, three‐dimensional (3D)‐reconstruction of sections to visualize morphology and a 3D‐measurement scheme to build local morphogenetic information. Although thick the section confocal microscopy partially solves these issues, information loss at the section surface hampers the reconstruction of 3D morphology. Episcopic imaging provides the correct morphology but lacks histological procedures to identify multiple cell types. The 3D‐measurement scheme is based on systematic sampling, with overlapping sample volumes, of the entire organ in the aligned image stack. For each sample volume, morphogenetic variables are calculated and results projected back to the cube (boxel) at the sample volume center. Boxel size determines spatial resolution of the final quantitative 3D‐reconstruction whereas size of the sample volume determines the precision of the morphogenetic information. The methods described here can be used to measure tissue volume, proliferation and cell size, to determine contribution and distribution of cell types in a tissue and to display this information in a quantitative 3D‐reconstruction. Anat Rec, 302:49–57, 2019. © 2018 Wiley Periodicals, Inc.

International audience; We conduct a thorough study of photomet-ric stereo under nearby point light source illumination, from modeling to numerical solution, through calibration. In the classical formulation of photometric stereo, the luminous fluxes are assumed to be directional, which is very difficult to achieve in practice. Rather, we use light-emitting diodes (LEDs) to illuminate the scene to be reconstructed. Such point light sources are very convenient to use, yet they yield a more complex photo-metric stereo model which is arduous to solve. We first derive in a physically sound manner this model, and show how to calibrate its parameters. Then, we discuss two state-of-the-art numerical solutions. The first one alternatingly estimates the albedo and the normals, and then integrates the normals into a depth map. It is shown empirically to be independent from the ini-tialization, but convergence of this sequential approach is not established. The second one directly recovers the depth, by formulating photometric stereo as a system of nonlinear partial differential equations (PDEs), which are linearized using image ratios. Although the sequential approach is avoided, initialization matters a lot and convergence is not established either. Therefore, we introduce a provably convergent alternating reweighted least-squares scheme for solving the original system of nonlinear PDEs. Finally, we extend this study to the case of RGB images.

The thoracic morphology of the troglobiontic leiodid species Troglocharinus ferreri (Cholevinae, Leptodirini) is described and documented in detail. The features are mainly discussed with respect to modifications linked with subterranean habits. Troglocharinus is assigned to the moderately modified pholeuonoid morphotype. The body is elongated and slender compared to epigean leiodids and also cave-dwelling species of Ptomaphagini. The legs are elongated, especially the hindlegs, though to a lesser degree than in the most advanced troglobiontic species. The prothorax is moderately elongated but otherwise largely unmodified. Its muscular system is strongly developed, with more muscle bundles that in free-living staphylinoid or hydrophiloid species. The pterothorax is greatly modified, especially the metathoracic flight apparatus. The meso- and metathoracic elements of the elytral locking device are well-developed, whereas the other notal parts are largely reduced. The mesonotum is simplified, with the triangular scutellar shield as the only distinctly developed part. The mesothoracic musculature is strongly reduced, with only 6 muscles compared to 12 or 13 in free-living staphylinoid or hydrophiloid species. The metanotum is greatly reduced, without a recognizable subdivision into prescutum scutum and scutellum. It is strongly narrowing laterally and lacks notal wing processes and other wing-related elements, but well-developed alacristae are present. The wings are reduced to small membranous flap-like structures inserted at the posterior end of the metanotum. A metapostnotum is not developed. Like in the case of the head, cave dwelling species of the related Ptomaphagini and Leptodirini show different trends of adaptations, with a compact ovoid or navicular body shape in the former, and a distinct trend towards elongation of the body and appendages in the latter tribe. Structural affinities of the thoraces of T. ferreri and the troglobiontic trechine carabid Sinaphaenops wangorum are mainly due to the reduced flight apparatus. The degree of muscle reduction in the pterothorax is very similar in both species., Our work was partly funded by project CGL2013-48950-C2 (AEI/FEDER, UE). The first author wants to express his thanks to CSC (No. 201708440281).

The reproductive system of spider crabs (Majoidea) has raised considerable interest due to the complexity of female sperm storage organs. In several majoid species, the seminal receptacle has been described as being divided into a dorsal storage chamber and a ventral fertilization chamber separated by a muscular velum. The velum is supposed to control the amount of sperm used for fertilization and to play an important role in sperm competition. Here, we present a study on the reproductive systems of the two majoid species, Mithraculus sculptus (Lamarck, 1818) and Stenorhynchus seticornis (Herbst, 1788) using various morphological techniques such as μCT scans and 3D-reconstructions, complemented by paraffin histology. The male gonopods of the herein investigated species are similar in their general morphology and in the presence and distribution of setae. The tubular first gonopod holding the ejaculatory canal is much longer than the short and stout second gonopod, which is supposed to function as a piston in the transport of sperm into the female ducts. The female reproductive system of M. sculptus and S. seticornis conforms to that of other Eubrachyura in possessing paired ovaries, oviducts, seminal receptacles, vaginae, and vulvae. Based on our 3D-reconstructions we demonstrate that there is no division of the seminal receptacle into two chambers separated by a velum. In contrast to this, we observed a spatially restricted invagination of the seminal receptacle. A comparison of our data with those of previous studies, allows for the conclusion that the invagination of the seminal receptacle may have been misinterpreted and mistaken for a velum by other authors. Thus, the division of the seminal receptacle into two chambers separated by a velum is a character which needs to be re-evaluated.

Adult head structures are well known in the coleopteran suborders Archostemata and Adephaga, whereas the available information is very fragmentary in the megadiverse Polyphaga, including the successful superfamily Staphylinoidea. In the present study, the cephalic morphology of the cholevine species Catops ventricosus is described in detail and documented. The results were compared to conditions occurring in other polyphagan lineages, especially staphylinoid and scarabaeoid representatives. Specific external features documented in Catops and potential autapomorphies of Leiodidae include a five-segmented antennal club with a reduced eighth antennomere and the presence of periarticular grooves filled with sensilla on antennomeres 7, 9, and 10. The firm connection of the head and pronotum is possibly an apomorphy of Cholevinae. The monophyly of Cholevinae excluding Eucatopini and Oritocatopini is supported by the apical maxillary palpomere as long as or shorter than the subapical one, and the presence of cryptic pore plates on the surface of these palpomeres—a feature described and documented here for the first time. The internal cephalic structures of Catops are mostly plesiomorphic, as for instance the complete tentorium. The pattern of the muscles is similar to what is found in other staphylinoid taxa. The unusual maxillary muscle “Mx” is likely a groundplan apomorphy of the clade Staphyliniformia + Scarabaeoidea. M. hypopharyngomandibularis (M13) was identified in Catops and is ancestral for Coleoptera, even though it is often missing. The same applies to M. tentoriohypopharyngalis (M42)., The PhD study of CAC as well as his research internship at the Friedrich-Schiller-Universität was funded by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) (2012/19002-0 and 2014/22088-0). PG was also supported by FAPESP (2013/06314-7) and MY by the DAAD, which is also gratefully acknowledged. The stay of IR in the Phyletisches Museum in Jena was funded by a Salvador de Madariaga grant (PRX14/00583).

PURPOSE The purpose of this study was to identify the complex course of the mandibular canal using 3D reconstruction of microCT images and to provide the diagram for clinicians to help them understand at the interforaminal region in Korean. MATERIALS AND METHODS Twenty-six hemimandibles obtained from cadavers were examined using microCT, and the images were reconstructed. At both the midpoint of mental foramen and the tip of anterior loop, the bucco-lingual position, the height from the mandibular inferior border, the horizontal distance between two points, and position relative to tooth site on the mandibular canal were measured. The angle that the mental canal diverges from the mandibular canal was measured in posteriorsuperior and lateral-superior direction. RESULTS The buccal distance from the mandibular canal was significantly much shorter than lingual distance at both the mental foramen and the tip of anterior loop. The mandibular canal at the tip of anterior loop was significantly located closer to buccal side and higher than at the mental foramen. And the mental canal most commonly diverged from the mandibular canal below the first premolar by approximately 50° posterior-superior and 41° lateral-superior direction, which had with a mean length of 5.19 mm in front of the mental foramen, and exited to the mental foramen below the second premolar. CONCLUSION These results suggest that it could form a hazardous tetrahedron space at the interforaminal region, thus, the clinician need to pay attention to the width of a premolar tooth from the mental foramen during dental implant placement.

International audience; We improve the depth map provided by an RGB-D sensor, using color photometric stereo. The sensor is equipped with three colored LEDs, in order for thinnest geometric details to be recovered from the RGB image by photometric stereo. This thin shape estimate is thensed with the depth map provided by the sensor, through a variational approach to photometric stereo dedicated to anisotropic point light sources of LED type.; Nous montrons comment utiliser la stéréophotométrie colorée pour améliorer le relief fourni par un capteur RVB-D. Le capteur est équipé de trois LEDs colorées, de telle sorte que l'image RVB permet de retrouver les détails les plus fins du relief, grâce à la stéréophotométrie. Cette estimation fine du relief est fusionnée avec la carte de profondeur fournie par le capteur, grâce à une nouvelle approche différentielle et variationnelle de la stéréophotométrie adaptée aux sources ponctuelles anisotropes de type LED. Cetta approche permet d'estimer la profon-deur directement et de façon robuste, sans estimation préalable des normales et de l'albédo. ABSTRACT. We improve the depth map provided by an RGB-D sensor, using color photometric stereo. The sensor is equipped with three colored LEDs, in order for thinnest geometric details to be recovered from the RGB image by photometric stereo. This thin shape estimate is then fused with the depth map provided by the sensor, through a variational approach to photometric stereo dedicated to anisotropic point light sources of LED type. MOTS-CLÉS : reconstruction 3D, stéréophotométrie, capteurs RVB-D, méthodes variationnelles.

A distinctive feature of embryonic tendon development is the steady increase in collagen fibril diameter and associated improvement of tissue mechanical properties. A potential mechanical stimulus for these changes is slow stretching of the tendon during limb growth. Testing this hypothesis in vivo is complicated by the presence of other developmental processes including muscle development and innervation. Here we used a cell culture tendon-like construct to determine if slow stretch can explain the increases in fibril diameter and mechanical properties that are observed in vivo. Non-stretched constructs had an ultrastructural appearance and mechanical properties similar to those of early embryonic tendon. However, slowly stretching during 4 days in culture increased collagen fibril diameter, fibril packing volume, and mechanical stiffness, and thereby mimicked embryonic development. 3D EM showed cells with improved longitudinal alignment and elongated nuclei, which raises the hypothesis that nuclear deformation could be a novel mechanism during tendon development. Developmental Dynamics 240:2520–2528, 2011. © 2011 Wiley Periodicals, Inc.

The first description of the presence of a utriculo-endolymphatic valve in human fetuses was given by Bast in 1928. Since then this valve-like structure is called Bast's valve. Its exact function has not yet been established. The general opinion is that it has a protective function by having the possibility to separate the superior endolymphatic compartments of the labyrinth from the inferior compartment. Phylogenetically seen birds are the first vertebrates with a cochlear duct and a distinct inferior and superior part of the labyrinth. A structure in the pigeon inner ear, resembling Bast's valve in mammals, is described.

This thesis tackles the photometric stereo problem, a 3D-reconstruction technique consisting in taking several pictures of a scene under different lightings. We first focus on robust techniques for estimating the normals to the surface, and for integrating these normals into a depth map. Then, we study two situations where the problem is ill-posed: when lightings are unknown and when only two images are used. Part 3 is devoted to more realistic models, in terms of lightings and of surface reflectance. These first three parts bring us to the limits of the usual formulation of photometric stereo: we eventually introduce in Part 4 a variational and differential reformulation of this problem which allows us to overcome these limits.; Cette thèse traite de la reconstruction 3D par stéréophotométrie, qui consiste à utiliser plusieurs photographies d’une scène prises sous le même angle, mais sous différents éclairages. Nous nous intéressons dans un premier temps à des techniques robustes pour l’estimation des normales à la surface, et pour leur intégration en une carte de profondeur. Nous étudions ensuite deux situations où le problème est mal posé : lorsque les éclairages sont inconnus, ou lorsque seuls deux éclairages sont utilisés. La troisième partie est consacrée à l’étude de modèles plus réalistes, à la fois en ce qui concerne les éclairages et la réflectance de la surface. Ces trois premières parties nous amènent aux limites de la formulation classique de la stéréophotométrie : nous introduisons finalement, dans la partie 4, une reformulation variationnelle et différentielle du problème qui permet de dépasser ces limites.

PVD hard coatings are continuously gaining their importance in different fields of applications. In industrial use, they are often exposed to corrosive environments. Hard coatings possess inherently good corrosion resistance, but the substrate-hard coating systems may suffer from a severe corrosion attack due to the defects (craters, pin holes) in the coatings. On the sites, where defects extend through the coating, pitting corrosion can take place. These sites are drawbacks in the applications of hard coating. A PVD TiAlN hard coating was prepared on cold-work, tool-steel (AISI D2) substrates by sputtering using unbalanced magnetron sources. The growth defects incorporated into the coating were studied after the deposition and corrosion experiments. We used two methods: (1) scanning electron microscopy (SEM) for general overview of the coating topography and 2D-characterization of defects, and (2) scanning electron microscopy with a focused ion beam (SEM-FIB) for making serial cross-sections through the selected defects in order to provide images for a 3D-reconstruction of defects. In this work we tried to investigate the formation of a defect at a specific location and findout whether the selected defect causes pitting corrosion. PVD trde prevleke pridobivajo pomen na različnih področjih uporabe. Pri različnih aplikacijah so pogosto izpostavljene korozijskemu okolju. Trde prevleke so kemijsko inertne in same po sebi korozijsko obstojne. Med njihovo pripravo pa nastane v njih veliko defektov (kraterji, "pinholi"). Nekateri od njih segajo do podlage. Na teh mestih pride do jamičaste korozije, kar pa je z vidika uporabe neželeno. TiAlN-prevleko smo nanesli na podlago orodnega jekla D2 po postopku naprševanja z neuravnoteženim magnetronskim izvirom. Defekte, ki so nastali med pripravo plasti, smo preučili po korozijskem preizkusu. Za analizo smo uporabili dve metodi. Vrstični elektronski mikroskop(SEM), s katerim smo pridobili splošni pregled prevleke, kot tudi 2D-karakterizacijo defektov. Kot drugo metodo smo uporabili fokusiran ionski curek, ki je integriran v klasični SEM, s katerim smo izvedli serijo rezov izbranih defektov za njihovo 3D-karakterizacijo. V delu smo poskušali na specifičnih mestih ugotoviti mehanizem nastanka defektov in ugotovljali, ali povzročajo jamičasto korozijo.

The gastrointestinal tract is one of the major sites of immunological challenges in biology. Therefore its study is very necessary for a better understanding of the biological processes that take place, in order to be used in the study of colon diseases such as colonic polyps, ulcerative colitis, diverticulitis, irritable bowel syndrome or colon cancer. In vivo studies of small animals are key to improving human diagnosis. Despite the importance of clinical trials, they have many limitations such as in vivo imaging, which allows better understanding of biology and diseases. In vivo imaging is consider visual representation, characterization, and quantification of biological processes at the cellular and subcellular levels within intact living organisms. But not all the imaging techniques have good resolution so the research of develop better high resolution techniques enhances biological studies. so this project is trying to increase resolution and acquisition efficiency of colon imaging. Based on in vivo imaging of small animals, the aim of this work is the image acquisition, and image processing of a multimodal infrared fluorescence endoscopy. This endoscope consists on two cameras: one of white light and the other of infrared light; that allow fluorescence imaging, giving a lot of information of the sample, such as the detection of cancer markers. A separate scanning confocal unit, that enables of cellular examinations of the colon, part of other bachelor's degree thesis of Isabel Martin Civiac. Image acquisition is based on a motorized bed for the sample, allowing slowly control insertion of the endoscope into the sample. With respect to image processing, the obtained images are reconstructed to give 3D images with respect the depth to offer full 3D information. Ingeniería Biomédica

International audience; Estimating the shape and appearance of an object, given one or several images, is still an open and challenging research problem called 3D-reconstruction. Among the different techniques available, photometric stereo (PS) produces highly accurate results when the lighting conditions have been identified. When these conditions are unknown, the problem becomes the so-called uncalibrated PS problem, which is ill-posed. In this paper, we will show how total variation can be used to reduce the ambiguities of uncalibrated PS, and we will study two methods for estimating the parameters of the generalized bas-relief ambiguity. These methods will be evaluated through the 3D-reconstruction of real-world objects.

11 pages, 2 figures.-- PMID: 15477099 [PubMed].-- Printed version published on Nov 2004., X-windows based microscopy image processing package (Xmipp) is a specialized suit of image processing programs, primarily aimed at obtaining the 3D reconstruction of biological specimens from large sets of projection images acquired by transmission electron microscopy. This public-domain software package was introduced to the electron microscopy field eight years ago, and since then it has changed drastically. New methodologies for the analysis of single-particle projection images have been added to classification, contrast transfer function correction, angular assignment, 3D reconstruction, reconstruction of crystals, etc. In addition, the package has been extended with functionalities for 2D crystal and electron tomography data. Furthermore, its current implementation in C++, with a highly modular design of well-documented data structures and functions, offers a convenient environment for the development of novel algorithms. In this paper, we present a general overview of a new generation of Xmipp that has been re-engineered to maximize flexibility and modularity, potentially facilitating its integration in future standardization efforts in the field. Moreover, by focusing on those developments that distinguish Xmipp from other packages available, we illustrate its added value to the electron microscopy community., We acknowledge partial support from the "Comunidad Autónoma de Madrid" through Grant CAM-07B-0032-2002, the "Comisión Interministerial de Ciencia y Tecnología" of Spain through Grants BIO2001-1237, BIO2001-4253-E, BIO2001-4339-E, and BIO2002-10855-E, the European Union through Grants QLK2-2000-00634, QLRI-2000-31237, QLRT-2000-0136, and QLRI-2001-00015, and the NIH through Grant HL70472. Partial support from the "Universidad San Pablo-CEU" Grant 17/02 is also acknowledged.

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University London. Virtual camera realisation and the proposition of trapezoidal camera architecture are the two broad contributions of this thesis. Firstly, multiple camera and their arrangement constitute a critical component which affect the integrity of visual content acquisition for multi-view video. Currently, linear, convergence, and divergence arrays are the prominent camera topologies adopted. However, the large number of cameras required and their synchronisation are two of prominent challenges usually encountered. The use of virtual cameras can significantly reduce the number of physical cameras used with respect to any of the known camera structures, hence adequately reducing some of the other implementation issues. This thesis explores to use image-based rendering with and without geometry in the implementations leading to the realisation of virtual cameras. The virtual camera implementation was carried out from the perspective of depth map (geometry) and use of multiple image samples (no geometry). Prior to the virtual camera realisation, the generation of depth map was investigated using region match measures widely known for solving image point correspondence problem. The constructed depth maps have been compare with the ones generated using the dynamic programming approach. In both the geometry and no geometry approaches, the virtual cameras lead to the rendering of views from a textured depth map, construction of 3D panoramic image of a scene by stitching multiple image samples and performing superposition on them, and computation of virtual scene from a stereo pair of panoramic images. The quality of these rendered images were assessed through the use of either objective or subjective analysis in Imatest software. Further more, metric reconstruction of a scene was performed by re-projection of the pixel points from multiple image samples with a single centre of projection. This was done using sparse bundle adjustment algorithm. The statistical summary obtained after the application of this algorithm provides a gauge for the efficiency of the optimisation step. The optimised data was then visualised in Meshlab software environment, hence providing the reconstructed scene. Secondly, with any of the well-established camera arrangements, all cameras are usually constrained to the same horizontal plane. Therefore, occlusion becomes an extremely challenging problem, and a robust camera set-up is required in order to resolve strongly the hidden part of any scene objects. To adequately meet the visibility condition for scene objects and given that occlusion of the same scene objects can occur, a multi-plane camera structure is highly desirable. Therefore, this thesis also explore trapezoidal camera structure for image acquisition. The approach here is to assess the feasibility and potential of several physical cameras of the same model being sparsely arranged on the edge of an efficient trapezoid graph. This is implemented both Matlab and Maya. The quality of the depth maps rendered in Matlab are better in Quality.

Tracking a moving object and reconstructing its trajectory can be done with a stereo camera system, since the two cameras enable depth vision. However, such a system would not work if one of the cameras fails to detect the object. If that happens, it would be beneficial if the system could still use the functioning camera to make an approximate trajectory reconstruction. In this study, I have investigated how past observations from a stereo system can be used to recreate trajectories when video from only one of the cameras is available. Several approaches have been implemented and tested, with varying results. The best method was found to be a nearest neighbors-search optimized by a Kalman filter. On a test set with 10000 golf shots, the algorithm was able to create estimations which on average differed around 3.5 meters from the correct trajectory, with better results for trajec-tories originating close to the camera. Att spåra ett objekt i rörelse och rekonstruera dess bana kan göras med ett stereokamerasystem, eftersom de två kamerorna möjliggör djupseende. Ett sådant system skulle dock inte fungera om en av kamerorna misslyckas med att detektera objektet. Om det händer skulle det vara fördelaktigt om systemet ändå kunde använda den fungerande kameran för att göra en approximativ rekonstruktion av banan. I den här studien har jag undersökt hur tidigare observationer från ett stereosystem kan användas för att rekonstruera banor när video från enbart en av kamerorna är tillgänglig. Ett flertal metoder har implementerats och testats, med varierande resultat. Den bästa metoden visade sig vara en närmaste-grannar-sökning optimerad med ett Kalman-filter. På en testmängd bestående av 10000 golfslag kunde algoritmen skapa uppskattningar som i genomsnitt skiljde sig 3.5 meter från den korrekta banan, med bättre resultat för banor som startat nära kameran.

© 2015, Springer Science+Business Media New York. This paper presents CCMM (acronym for image Clique Matching), a new deterministic algorithm for the visual feature matching problem when images have low distortion. CCMM is multi-hypothesis, i.e. for each feature to be matched in the original image it builds an association graph which captures pairwise compatibility with a subset of candidate features in the target image. It then solves optimum joint compatibility by searching for a maximum clique. CCMM is shown to be more robust than traditional RANSAC-based single-hypothesis approaches. Moreover, the order of the graph grows linearly with the number of hypothesis, which keeps computational requirements bounded for real life applications such as UAV image mosaicing or digital terrain model extraction. The paper also includes extensive empirical validation., This work is funded by the Spanish Ministry of Economy and Competitiveness (ARABOT: DPI 2010-21247-C02-01) and supervised by CACSA whose kindness we gratefully acknowledge.

Tracking a moving object and reconstructing its trajectory can be done with a stereo camera system, since the two cameras enable depth vision. However, such a system would not work if one of the cameras fails to detect the object. If that happens, it would be beneficial if the system could still use the functioning camera to make an approximate trajectory reconstruction. In this study, I have investigated how past observations from a stereo system can be used to recreate trajectories when video from only one of the cameras is available. Several approaches have been implemented and tested, with varying results. The best method was found to be a nearest neighbors-search optimized by a Kalman filter. On a test set with 10000 golf shots, the algorithm was able to create estimations which on average differed around 3.5 meters from the correct trajectory, with better results for trajec-tories originating close to the camera. Att spåra ett objekt i rörelse och rekonstruera dess bana kan göras med ett stereokamerasystem, eftersom de två kamerorna möjliggör djupseende. Ett sådant system skulle dock inte fungera om en av kamerorna misslyckas med att detektera objektet. Om det händer skulle det vara fördelaktigt om systemet ändå kunde använda den fungerande kameran för att göra en approximativ rekonstruktion av banan. I den här studien har jag undersökt hur tidigare observationer från ett stereosystem kan användas för att rekonstruera banor när video från enbart en av kamerorna är tillgänglig. Ett flertal metoder har implementerats och testats, med varierande resultat. Den bästa metoden visade sig vara en närmaste-grannar-sökning optimerad med ett Kalman-filter. På en testmängd bestående av 10000 golfslag kunde algoritmen skapa uppskattningar som i genomsnitt skiljde sig 3.5 meter från den korrekta banan, med bättre resultat för banor som startat nära kameran.

We report on the workflow for the creation of realistic virtual anthropomorphic characters. 3D-models of human heads have been reconstructed from real people by following a structured light approach to 3D-reconstruction. We describe how these high-resolution models have been simplified and articulated with blend shape and mesh skinning techniques to ensure real-time animation. The full-body models have been created manually based on photographs. We present a system for capturing whole body motions, including the fingers, based on an optical motion capture system with 6 DOF rigid bodies and cybergloves. The motion capture data was processed in one system, mapped to a virtual character and visualized in real-time. We developed tools and methods for quick post processing. To demonstrate the viability of our system, we captured a library consisting of more than 90 gestures.

Visual procedures especially tailored to the constraints and requirements of a legged robot are presented. They work for an uncalibrated camera, with pan and zoom, freely moving towards a stationary target in an unstructured environment that may contain independently moving objects. The goal is to dynamically analyse the image sequence in order to extract information about the robot motion, the target position and the environment structure. The development is based on the deformations of an active contour fitted to the target. Experimental results confirm that the proposed approach constitutes a promising alternative to the prevailing trend based on the costly computation of displacement or velocity fields., This work was supported by the project 'Navegación basada en visión de robots autónomos en entornos no estructurados.' (070-724).

In this thesis we study the problem of multi-session dense rgb-d slam for 3D reconstruc- tion. Multi-session reconstruction can allow users to capture parts of an object that could not easily be captured in one session, due for instance to poor accessibility or user mistakes. We first present a thorough overview of single-session dense rgb-d slam and describe the multi-session problem as a loosening of the incremental camera movement and static scene assumptions commonly held in the single-session case. We then implement and evaluate sev- eral variations on a system for doing two-session reconstruction as an extension to a single- session dense rgb-d slam system. The extension from one to several sessions is divided into registering separate sessions into a single reference frame, re-optimizing the camera trajectories, and fusing together the data to generate a final 3D model. Registration is done by matching reconstructed models from the separate sessions using one of two adaptations on a 3D object detection pipeline. The registration pipelines are evaluated with many different sub-steps on a challenging dataset and it is found that robust registration can be achieved using the proposed methods on scenes without degenerate shape symmetry. In particular we find that using plane matches between two sessions as constraints for as much as possible of the registration pipeline improves results. Several different strategies for re-optimizing camera trajectories using data from both ses- sions are implemented and evaluated. The re-optimization strategies are based on re- tracking the camera poses from all sessions together, and then optionally optimizing over the full problem as represented on a pose-graph. The camera tracking is done by incrementally building and tracking against a tsdf volume, from which a final 3D mesh model is extracted. The whole system is qualitatively evaluated against a realistic dataset for multi-session re- construction. It is concluded that the overall approach is successful in reconstructing objects from several sessions, but that other fine grained registration methods would be required in order to achieve multi-session reconstructions that are indistinguishable from singe-session results in terms of reconstruction quality.

Искусство и культура. - 2014. - № 3. - С. 73-77. - Библиогр.: с. 77 (3 назв.)., Авторы статьи рассматривают вопрос использования компьютерных возможностей 3D-реконструкции в исторической науке. На примере древнего Витебска показываются, как можно воссоздать облик города с использованием компьютерного моделирования. Авторы уже воссоздали древнее балтское городище на горе Ломиха, которая располагалась ранее в центре современного Витебска, показали, какие сложности могут возникнуть при моделировании древних построек, ландшафтов, указали на то, что далеко не всегда данные археологии позволяют воссоздать первоначальный облик древних построек. Предполагается, что итогом работы над проектом станет создание мультимедийного продукта, который можно будет использовать в качестве учебного материала, основы для создания видеофильмов, иллюстраций для учебников, путеводителей, компьютерных игр по исторической тематике. Также авторы определили основные этапы истории города, которые стоит визуализировать при помощи компьютерных технологий. = The authors examine the issue of applying computer possibilities of 3D-reconstruction in historical science. On the example of ancient Vitebsk it is shown how the look of the city can be recreated using computer simulations. The authors have already recreated an ancient fort on Baltic Mount of Lomiha which was earlier located in the center of modern Vitebsk and showed what difficulties may arise in the simulation of ancient buildings, landscapes, pointed out that the data do not always allow archeology to recreate the original appearance of ancient buildings. It is assumed that the outcome of the project will be the creation of a multimedia product that can be used as teaching material basis for the creation of videos, illustrations for books, travel guides, computer games on historical topics. The authors also identified the main stages of the history of the city that are worth visualizing with the application of computer technology.

Here, we describe a robust method for mapping the number and type of neuro-chemically distinct synaptic inputs that a single reconstructed neuron receives. We have used individual hypoglossal motor neurons filled with Neurobiotin by semi-loose seal electroporation in thick brainstem slices. These filled motor neurons were then processed for excitatory and inhibitory synaptic inputs, using immunohistochemical-labeling procedures. For excitatory synapses, we used anti-VGLUT2 to locate glutamatergic pre-synaptic terminals and anti-PSD-95 to locate post-synaptic specializations on and within the surface of these filled motor neurons. For inhibitory synapses, we used anti-VGAT to locate GABAergic pre-synaptic terminals and anti-GABA-A receptor subunit α1 to locate the post-synaptic domain. The Neurobiotin-filled and immuno-labeled motor neuron was then processed for optical sectioning using confocal microscopy. The morphology of the motor neuron including its dendritic tree and the distribution of excitatory and inhibitory synapses were then determined by three-dimensional reconstruction using IMARIS software (Bitplane). Using surface rendering, fluorescence thresholding, and masking of unwanted immuno-labeling, tools found in IMARIS, we were able to obtain an accurate 3D structure of an individual neuron including the number and location of its glutamatergic and GABAergic synaptic inputs. The power of this method allows for a rapid morphological confirmation of the post-synaptic responses recorded by patch-clamp prior to Neurobiotin filling. Finally, we show that this method can be adapted to super-resolution microscopy techniques, which will enhance its applicability to the study of neural circuits at the level of synapses.

The dendritic spines on pyramidal cells represent the main postsynaptic elements of cortical excitatory synapses and they are fundamental structures in memory, learning and cognition. In the present study, we used intracellular injections of Lucifer yellow in fixed tissue to analyse over 19 500 dendritic spines that were completely reconstructed in three dimensions along the length of the basal dendrites of pyramidal neurons in the parahippocampal cortex and CA1 of patients with Alzheimer's disease. Following intracellular injection, sections were immunostained for anti-Lucifer yellow and with tau monoclonal antibodies AT8 and PHF-1, which recognize tau phosphorylated at Ser202/Thr205 and at Ser396/404, respectively. We observed that the diffuse accumulation of phospho-tau in a putative pre-tangle state did not induce changes in the dendrites of pyramidal neurons, whereas the presence of tau aggregates forming intraneuronal neurofibrillary tangles was associated with progressive alteration of dendritic spines (loss of dendritic spines and changes in their morphology) and dendrite atrophy, depending on the degree of tangle development. Thus, the presence of phospho-tau in neurons does not necessarily mean that they suffer severe and irreversible effects as thought previously but rather, the characteristic cognitive impairment in Alzheimer's disease is likely to depend on the relative number of neurons that have well developed tangles. © 2013 The Author., CIBERNED (CB06/05/0066), Fundación CIEN (Financiación de Proyectos de Investigación de Enfermedad de Alzheimer enfermedades relacionadas 2008), Fundación Caixa (BM05-47-0) and the Spanish Ministry of Economy and Competitiveness (SAF2009-09394 and BFU2012-34963).

The study presented here shows the development of Antedon bifida starting with the doliolaria larva until juvenile stage based on ultrastructural and lightmicroscopical data. 3d-reconstructions of a doliolaria and of three young cystidean stages as well as a juvenile have been done. The related data have been complemented by serial sections of older cystidean and pentacrinoid stages. Special attention has been given to the development of the “ventral structures” in interradius CD, to the development of the axocoel and the fate of both the left and the right somatocoel. The fusion processes of these three coeloms as well as their potential contribution to the formation of the axial sinus (=axial coelom) and its associated hemal organs of the adult are investigated. Part of the “ventral structures” in interradius CD are the primary stone canal, which is sent out by the hydrocoel, as well as the axocoel and the small ventral coelom, whose formation is traced in this thesis. Furthermore, there is a ventral mesenteric formation, which derives from the horizontal mesentery and from whose coelothelia the potential primary gonadal cells (PGCs) are formed. Enclosed in the ventral mesenteric formation resides the ventral lacuna, which is partially formed by cell protrusions sent out by the small ventral coelom’s coelothel and also bordered by the nearby coeloms. Structural and positional characteristics of the PGCs, the small ventral coelom and the ventral lacuna support the assumption that these are parts of a primary gonad anlage, whose fate in the adult is, however, unclear. In contrast to former findings in Antedon mediterranea, the axocoel in the cystidean larva of A. bifida forms a process around the esophagus that may even become annular. The possibility is discussed in this thesis that this axocoelomic process takes part in fusion processes and that it is involved in formation of the periesophageal lacuna that extends on the right side of the esophagus from the ventral lacuna to the oral end of the glandular axial organ. The intimate proximity of the axocoelomic periesophageal process to the oral end of the glandular axial organ’s hemal sinus corroborates the widely accepted assumption that the latter is homologous to the axial organ of asterioids, ophiuroids and echinoids (AOE) and also supports an homology of the AOE axial organ to the Reichensperger’s organ of certain sea lily species (Isocrinida, Calamocrinus diomedae). The primarily formed larval lacunae can be traced back to the mesenteries dissolved during the fusion processes. In this thesis, marker structures are defined, that allow tracing the development and the fate of the coeloms up to juvenile stage and may possibly also give an orientation in the adult. The detailed investigation of mesenteric remnants in older larval stages and in the juvenile furthermore shows that the left somatocoel extends aborally within the innermost intestinal coil (axial compartment). This is probably enabled by an inward directed tilting of the gut during intestinal outgrowth. Where the left and the right somatocoel come to lie against each other, a new mesentery forms, from whose extracellular matrix the hemal sinus originates. The present data support the heretofore proposed initial formation of the epithelial tubule of the glandular axial organ as a delamination of a cell strand from the coelothelium of the right somatocoel in intimate proximity to the proximal end of the prospective chambered organ in the doliolaria. However, a continued delamination from the right somatocoelothel, as assumed until now, is highly unlikely. The present data suggest that the tubule achieves an epithelial organization in the oralmost part of the prospective chambered organ and grows successively orally into the axial mesentery as well as aborally into the stalk. Based on the origin discussed for both the periesophageal lacuna and the glandular axial organ it can be shown, that the axial sinus is largely formed by the left somatocoel. Based on the present results, the coelothelium that rests on the hemal space of the spongy body, also derives from the left somatocoel., Die vorliegende Arbeit untersucht die Entwicklung von Antedon bifida von der Doliolarialarve bis zum Juvenilstadium basierend auf ultrastrukturellen und lichtmikroskopischen Daten. 3D-Rekonstruktionen einer Doliolaria und dreier junger Cystidienstadien sowie eines Juvenilstadiums wurden angefertigt und die zugehörigen Daten durch serielle Schnittserien von älteren Cystidien- und Pentacrinoidenstadien ergänzt. Besondere Beachtung finden die Entwicklung der „ventralen Strukturen“ im Interradius CD, die Entwicklung des Axocoels sowie das Schicksal des larvalen linken und rechten Somatocoels. Die Fusionsprozesse dieser drei Coelome sowie ihr möglicher Beitrag zur Bildung des Axialsinus (=Axialcoelom) und seiner assoziierten Hämalorgane im Adulttier werden untersucht. Zu den „ventralen Strukturen“ im Interradius CD gehören der vom Hydrocoel gebildete Steinkanal und das Axocoel, sowie ein kleines ventrales Coelom, dessen Bildung in dieser Arbeit nachvollzogen wird. Weiterhin findet sich hier eine ventrale mesenteriale Bildung, die sich vom horizontalen Mesenterium ableitet und aus deren Coelothelien die potentiellen primären Geschlechtszellen (PGCs) gebildet werden. In die ventrale mesenteriale Bildung eingebettet befindet sich die ventrale Lakune, die teilweise von Zellausläufern des Coelothels des kleinen ventralen Coeloms und zudem von den benachbarten Coelomen begrenzt wird. Strukturelle und räumliche Merkmale der PGCs, des kleinen ventralen Coeloms und der ventralen Lakune unterstützen die These, dass diese Teile einer primären Gonadenanlage sind, deren Verbleib im Adultus jedoch ungeklärt ist. Anders als bisher für Antedon mediterranea beschrieben, bildet das Axocoel in der Cystidienlarve von A. bifida einen Fortsatz um den Ösophagus, der vermutlich ringförmig auswächst. In der vorliegenden Arbeit wird die Möglichkeit diskutiert, dass dieser Axocoelfortsatz in die Verschmelzungsprozesse der Coelome der Larve mit einbezogen wird und an der Bildung der Perioesophageallakune beteiligt ist, welche auf der rechten Seite des Oesophagus von der Ventrallakune bis zum oralen Ende des glandulären Axialorganes verläuft. Die unmittelbare Nähe dieses Fortsatzes zum oberen Ende des Hämalsinus des glandulären Axialorganes untermauert die bestehende Vermutung, dass letzterer dem Hämalsinus des Axialorganes in Asteriden, Ophiuriden und Echiniden (AOE) homolog ist und unterstützt zudem die These einer Homologie des AOE-Axialorganes zum Reichensperger´schen Organ einiger Seelilienarten (Isocrinida, Calamomocrinus diomedae). Die zuerst auftretenden larvalen Lakunen können auf die während des Fusionsprozesses aufgelöste Mesenterien zurückgeführt werden. In der Arbeit werden Markerstrukturen definiert, anhand derer sich die Entwicklung und das Schicksal der Coelomräume bis zum Juvenilstadium verfolgen lassen und welche möglicherweise auch eine Orientierung im Adulttier geben können. Die eingehende Untersuchung der mesenterialen Überreste in älteren Larvenstadien und im Juvenilstadium zeigt zudem, dass das linke Somatocoel im Inneren der ersten intestinalen Windung (axiales Kompartiment) nach aboral, in Richtung gekammertes Organ reicht. Dies wird vermutlich durch eine in Totalpräparaten beobachtbare, nach innen gerichtete Kippung des Darmes während des Auswachsens ermöglicht. Dort wo das linke an das rechte Somatocoel angrenzt, bildet sich ein neues axiales Mesenterium, in dessen extracellulärer Matrix der Hämalsinus des Axialorganes geformt wird. Die vorliegenden Daten stützen die bereits beschriebene Bildung des epithelialen Schlauches des glandulären Axialorgans durch Delamination eines Zellstranges aus dem Coelothel des rechten Somatocoels am proximalen Ende des entstehenden gekammerten Organes in der Doliolaria. Allerdings ist eine fortschreitende Bildung aus der Wand des rechten Somatocoels, wie bisher angenommen, höchst unwahrscheinlich. Die vorliegenden Daten legen hingegen nahe, dass sich die Schlauchanlage zunächst im obersten Abschnitt des gekammerten Organes epithelial organisiert und dann sukzessive nach oral in das axiale Mesenterium und nach aboral in den Stiel auswächst. Aufgrund der diskutierten Herkunft der Perioesophageallakune und des glandulären Axialorganes lässt sich zeigen, dass der Axialsinus weitgehend vom Coelothel des linken Somatocoels gebildet wird. Das Coelothel, das dem den Axialsinus durchziehenden spongy body aufliegt, ist nach den vorliegenden Ergebnissen ebenfalls linken somatocoelen Ursprungs.

Introduction Traditionally, the origin of the third germ layer and its special formation of coelomic cavities by enterocoely is regarded to be an informative character in phylogenetic analyses. In early deuterostomes such as sea urchins, the mesoderm forms through a single evagination pinching off from the apical end of the archenteron which then gives off mesocoela and metacoela on each side. This echinoid-type coelom formation has conventionally been assumed to be ancestral for Deuterostomia. However, recent phylogenetic analyses show that Echinodermata hold a more derived position within Deuterostomia. In this regard a subgroup of Hemichordata, namely enteropneusts, seem to host promising candidates, because they are supposed to have retained many ancestral deuterostome features on the one hand, and furthermore share some characteristics with chordates on the other hand. In enteropneusts a wide range of different modes of coelom formation has been reported and in many cases authors of the original observations carefully detailed the limitations of their descriptions, while these doubts disappeared in subsequent reviews. In the present study, we investigated the development of all tissues in an enteropneust, Saccoglossus kowalevskii by using modern morphological techniques such as complete serial sectioning for LM and TEM, and 3D-reconstructions, in order to contribute new data to the elucidation of deuterostome evolution. Results Our data show that in the enteropneust S. kowalevskii all main coelomic cavities (single protocoel, paired mesocoela and metacoela) derive from the endoderm via enterocoely as separate evaginations, in contrast to the aforementioned echinoid-type. The anlagen of the first pair of gill slits emerge at the late kink stage (~96 h pf). From that time onwards, we documented a temporal left-first development of the gill slits and skeletal gill rods in S. kowalevskii until the 2 gill slit juvenile stage. Conclusions The condition of coelom formation from separate evaginations is recapitulated in the larva of amphioxus and can be observed in crinoid echinoderms in a similar way. Therefore, coelom formation from separated pouches, rather than from a single apical pouch with eventual subdivision is suggested as the ancestral type of coelom formation for Deuterostomia. Left-right asymmetries are also present in echinoderms (rudiment formation), cephalochordates (larval development), tunicates (gut coiling) and vertebrates (visceral organs), and it is known from other studies applying molecular genetic analyses that genes such as nodal, lefty and pitx are involved during development. We discuss our findings in S. kowalevskii in the light of morphological as well as molecular genetic data.