1,721,307 research outputs found
Supplementary files for "WingSegment: A Computer Vision-Based Hybrid Approach for Insect Wing Image Segmentation and 3D Printing"
No full text<p>WingSegment combines computer vision and graph theory to segment images of insect wings. The algorithm is supported by a user-friendly graphical interface created using Matlab App-designer. It allows for the identification of cells, junctions, Pterostigma, and venation patterns in insect wings. WingSegment employs region-growing, thinning, and Dijkstra's algorithms for boundary detection, junction identification, and vein path extraction. Additionally, it calculates geometric features such as the area, length, and circularity of cells, as well as the length of veins. The algorithm also generates histograms and box plots to visualize the measured geometric features. By utilizing cell centroids, WingSegment creates a Voronoi pattern on the wing. Furthermore, the detected boundaries can be exported as FreeCAD macro files, facilitating 3D modeling and further analysis. The accuracy and efficiency of WingSegment are validated through comparisons with established software tools and manual measurements, demonstrating its effectiveness. The results exhibit precise wing segmentation and enable in-depth analysis of wing properties. WingSegment contributes to the advancement of knowledge in insect wing morphology and its applications across various fields.</p>
Supporting files for "WingSegment: A Computer Vision-Based Hybrid Approach for Insect Wing Image Segmentation and 3D Printing"
No full text<p>WingSegment combines computer vision and graph theory to segment images of insect wings. The algorithm is supported by a user-friendly graphical interface created using Matlab App-designer. It allows for the identification of cells, junctions, Pterostigma, and venation patterns in insect wings. WingSegment employs region-growing, thinning, and Dijkstra's algorithms for boundary detection, junction identification, and vein path extraction. Additionally, it calculates geometric features such as the area, length, and circularity of cells, as well as the length of veins. The algorithm also generates histograms and box plots to visualize the measured geometric features. By utilizing cell centroids, WingSegment creates a Voronoi pattern on the wing. Furthermore, the detected boundaries can be exported as FreeCAD macro files, facilitating 3D modeling and further analysis. The accuracy and efficiency of WingSegment are validated through comparisons with established software tools and manual measurements, demonstrating its effectiveness. The results exhibit precise wing segmentation and enable in-depth analysis of wing properties. WingSegment contributes to the advancement of knowledge in insect wing morphology and its applications across various fields.</p>
Figure 9 in The morphological and functional variability of pleon-holding mechanisms in selected Eubrachyura (Crustacea: Decapoda)
No full textFigure 9. Pleon-holding mechanism of a juvenile Potamon fluviatile (Herbst, 1785), ♂, 11 × 9 mm, Greece, (ZMK1555), marked on a 3D volume reconstruction of the cuticle, based on µCT images. (a) Specimen complete, telson and sixth pleon segment in natural position. Arrow indicates location of pleon-holding structures. (b) Telson and sixth pleon segment moved from reconstruction into small inset. Buttons (red) visible inside the sterno-abdominal cavity, arrow on inset indicates position of pleonal socket. Note cuticular ridge next to telson. Orange: telson; red: buttons; yellow: pleon segment 6. Scale bar = 2 mm.Published as part of Köhnk, Stephanie, Gorb, Stanislav & Brandis, Dirk, 2017, The morphological and functional variability of pleon-holding mechanisms in selected Eubrachyura (Crustacea: Decapoda), pp. 2087-2132 in Journal of Natural History 51 (35-36) on page 2100, DOI: 10.1080/00222933.2017.1355076, http://zenodo.org/record/518345
The antenna of a burrowing dragonfly larva, Onychogomphus forcipatus (Anisoptera, Gomphidae)
No full textThe larva of the dragonfly Onychogomphus forcipatus (Anisoptera, Gomphidae) has a burrowing lifestyle and antennae composed of four short and broad segments (scape, pedicel and a two-segmented flagellum). The present ultrastructural investigation revealed that different sensilla and one gland are located on the antenna. There is a great diversity of mechanoreceptors of different kinds. In particular club-shaped sensilla, sensilla chaetica, and tree-like sensilla show the typical structure of bristles, the most common type of mechanoreceptors, usually responding to direct touch, while numerous long thin thorny trichoid sensilla show a morphology recalling the structure of filiform hair mechanoreceptors. The latter ones are presumably important in larval Odonata for current detection and rheotactic orientation, especially in a burrowing species. On the smooth apical cuticle of the second flagellar segment, three structures are visible: (1) a small ellipsoidal pit hosting a convoluted peg, the morphology of which resembles that of a typical chemoreceptor (even if pores are lacking), (2) a couple of small pits (not investigated under TEM), and (3) one wide depression with spherical structures, the internal morphology of which lets us assume that it is a gland with unknown function. This is the first report of an antennal gland in palaeopteran insects
Localization of Phenolic Compounds at an Air-Solid Interface in Plant Seed Mucilage: A Strategy to Maximize Its Biological Function?
No full textGiven a low concentration of phenols in the naturally occurring aqueous lubricant (mucilage) from hydrated seeds, their biological functions should be severely limited. Here, we introduce an undisclosed natural strategy that enables maximization of phenolic functions through exposing the phenols at the air-seed solid interface. Our findings not only offer a new perspective on plant reproduction physiology but also provide insights into an innovative design of lubricating biomaterials with additional phenolic functions.
Terminal contact elements of insect attachment devices studied by transmission X-ray microscopy
No full textFor the first time, the terminal elements (spatulae) of setal ( hairy) attachment devices of the beetle Gastrophysa viridula ( Coleoptera, Chrysomelidae) and the fly Lucilia caesar(Diptera, Calliphoridae) were studied using transmission X-ray microscopy (TXM) with a lateral resolution of about 30 nm. Since images are taken under ambient conditions, we demonstrate here that this method can be applied to study the contact behaviour of biological systems, including animal tenent setae, in a fresh state. We observed that the attached spatulae show a viscoelastic behavior increasing the contact area and providing improved adaptability to the local topography of the surface. The technique can be extended to TXM tomography, which would provide three-dimensional information and a deeper insight into the details of insect attachment structures
Not only for males: the pleon-holding mechanism in female calappids (Crustacea: Decapoda: Brachyura)
No full textContribution of individual legs to overall attachment in the adult ladybird Harmonia axyridis depends on the relative leg orientation to an external force
No full textThis study investigates the attachment ability of harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), focusing on the synergic action of opposite legs, the anisotropy of adhesive organs and sexual dimorphism. Contrary to expectations, experiments showed that beetles with fewer legs sometimes exhibited higher attachment forces, challenging the hypothesis that collective leg action enhances attachment. This result is attributed to differences in experimental set-ups, where our centrifugal method highlighted the importance of pad orientation relative to external
forces. The anisotropy of adhesive pads, characterized by the directional dependence of adhesion and friction, significantly influenced attachment performance. Results demonstrated that inward-oriented legs enhanced attachment due to lower peeling
angles, whereas outward orientation reduced effectiveness. Sexual dimorphism was evident in the structure of adhesive pads, with males possessing discoidal setae on fore- and midlegs. No significant difference in attachment was observed between
intact males and females on smooth surfaces, although ablated males sometimes showed higher forces due to the presence of discoidal setae. These findings underscore that attachment strength in H. axyridis is not solely dependent on pad area but also on the orientation and anisotropic properties of adhesive organs, as well as the specific role of sexual dimorphism in leg morphology
Anisotropic Friction: Bioinspired 3D Printed Locomotion Devices Based on Anisotropic Friction (Small 1/2019)
No full textLeaves that walk and eggs that stick: comparative functional morphology and evolution of the adhesive system of leaf insect eggs (Phasmatodea: Phylliidae)
Full text linkAbstract Phylliidae are herbivorous insects exhibiting impressive cryptic masquerade and are colloquially called “walking leaves”. They imitate angiosperm leaves and their eggs often resemble plant seeds structurally and in some cases functionally. Despite overall morphological similarity of adult Phylliidae, their eggs reveal a significant diversity in overall shape and exochorionic surface features. Previous studies have shown that the eggs of most Phylliidae possess a specialised attachment mechanism with hierarchical exochorionic fan-like structures (pinnae), which are mantled by a film of an adhesive secretion (glue). The folded pinnae and glue respond to water contact, with the fibrous pinnae expanding and the glue being capable of reversible liquefaction. In general, the eggs of phylliids appear to exhibit varying structures that were suggested to represent specific adaptations to the different environments the eggs are deposited in. Here, we investigated the diversity of phylliid eggs and the functional morphology of their exochorionic structure. Based on the examination of all phylliid taxa for which the eggs are known, we were able to characterise eleven different morphological types. We explored the adhesiveness of these different egg morphotypes and experimentally compared the attachment performance on a broad range of substrates with different surface roughness, surface chemistry and tested whether the adhesion is replicable after detachment in multiple cycles. Furthermore, we used molecular phylogenetic methods to reconstruct the evolutionary history of different egg types and their adhesive systems within this lineage, based on 53 phylliid taxa. Our results suggest that the egg morphology is congruent with the phylogenetic relationships within Phylliidae. The morphological differences are likely caused by adaptations to the specific environmental requirements for the particular clades, as the egg morphology has an influence on the performance regarding the surface roughness. Furthermore, we show that different pinnae and the adhesive glue evolved convergently in different species. While the evolution of the Phylliidae in general appears to be non-adaptive judging on the strong similarity of the adults and nymphs of most species, the eggs represent a stage with complex and rather diverse functional adaptations including mechanisms for both fixation and dispersal of the eggs
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