Systematics Review and Phylogeny of Cyrtophyllitinae Zeuner, 1935 sensu Gorochov, Jarzembowski & Coram, 2006 (Ensifera, Haglidae), with Description of Two New Species.

A phylogeny of Cyrtophyllitinae Zeuner, 1935 sensu Gorochov, Jarzembowski & Coram, 2006, based on wing morphology, is presented including all genera. Cyrtophillitinae is found to be paraphyletic. Except for Cyrtophyllites rogeri Oppenheim, 1888, all other species were moved from the subfamily Cyrtophyllitinae (Hagloidea, Haglidae). Consequently, a new subfamily Archaboilinae subfam. nov. was erected and accommodates most of the previous cyrtophillitine taxa, except Cyrtophyllites rogeri. The type genus Archaboilus Martynov, 1937 of the new subfamily was designated; a new genus, Pararchaboilus gen. nov., was erected with the designation of type species Pararchaboilus cretaceus comb. nov. From the Middle Jurassic deposits of China, two new species, Archaboilus ornatus sp. nov. and Vitimoilus gigantus sp. nov., are described.

Biomimetic Leaf-Vein Aerogel for Electromagnetic Wave Absorption and Thermal Superinsulation.

Electromagnetic protection in extreme environments requires materials with excellent thermal insulation capability and mechanical property to withstand severe temperature fluctuations and complex external stresses. Achieving strong electromagnetic wave absorption (EMA) while sustaining these exceptional properties remains a significant challenge. Herein, a facile approach is demonstrated to fabricate a biomimetic leaf-vein MXene/CNTs/PI (MCP) aerogel with parallel venations through bidirectional freeze-casting method. Due to its multi-arch lamellar structure and parallel venations within the aerogel layers, the ultralight MCP aerogel (16.9 mg·cm-3) achieves a minimum reflection loss (RLmin) of -75.8 dB and a maximum effective absorption bandwidth (EABmax) of 7.14 GHz with an absorber content of only 2.4 wt%, which also exhibits superelasticity and structural stability over a wide temperature range from -196 to 400 °C. Moreover, this unique structure facilitates rapid heat dissipation within the layers, while significantly impeding heat transfer between adjacent layers, achieving an ultralow thermal conductivity of 15.3 mW·m-1·K-1 for thermal superinsulation. The combination of excellent EMA performance, robust structural stability, and thermal superinsulation provides a potential design scheme under extreme conditions, especially in aerospace applications.

Comparative venation costs of monocotyledon and dicotyledon species in the eastern Colorado steppe.

MAIN CONCLUSION: Leaf vein network cost (total vein surface area per leaf volume) for major veins and vascular bundles did not differ between monocot and dicot species in 21 species from the eastern Colorado steppe. Dicots possessed significantly larger minor vein networks than monocots. Across the tree of life, there is evidence that dendritic vascular transport networks are optimized, balancing maximum speed and integrity of resource delivery with minimal resource investment in transport and infrastructure. Monocot venation, however, is not dendritic, and remains parallel down to the smallest vein orders with no space-filling capillary networks. Given this departure from the "optimized" dendritic network, one would assume that monocots are operating at a significant energetic disadvantage. In this study, we investigate whether monocot venation networks bear significantly greater carbon/construction costs per leaf volume than co-occurring dicots in the same ecosystem, and if so, what physiological or ecological advantage the monocot life form possesses to compensate for this deficit. Given that venation networks could also be optimized for leaf mechanical support or provide herbivory defense, we measured the vascular system of both monocot and dicots at three scales to distinguish between leaf investment in mechanical support (macroscopic vein), total transport and capacitance (vascular bundle), or exclusively water transport (xylem) for both parallel and dendritic venation networks. We observed that vein network cost (total vein surface area per leaf volume) for major veins and vascular bundles was not significantly different between monocot species and dicot species. Dicots, however, possess significantly larger minor vein networks than monocots. The 19 species subjected to gas-exchange measurement in the field displayed a broad range of Amax and but demonstrated no significant relationships with any metric of vascular network size in major or minor vein classes. Given that monocots do not seem to display any leaf hydraulic disadvantage relative to dicots, it remains an important research question why parallel venation (truly parallel, down to the smallest vessels) has not arisen more than once in the history of plant evolution.

The structure of wing in the earliest Permopsocida.

Permopsocids are small acercarian insects with mouthparts specialized for sucking. They are closely related to Hemiptera and Thysanoptera. The earliest known representatives are from the Early Permian. Here evidence is presented that the Permopsocida occurred even earlier in Pennsylvanian (Moscovian) deposits in the Piesberg quarry near Osnabrück (Lower Saxony, Germany). This material is assigned to the Permian family Psocidiidae; Carbonopsocus mercuryi gen. et sp. nov., based on the wing venation diagnosed by the unique branching pattern of the main veins, the shape of the areola postica being longer than wide, the angular shape of the pterostigma, the ir crossvein directed proximally mid of pterostigma (apomorphy) and the vannus formed by the three veins of PCu, A1 and A2. The shape of the veins, with a Y-vein formed by the distal fusion of PCu with A1, could be a putative symplesiomorphy of the Psocodea with Permopsocida and Hemiptera. C. mercuryi gen. et sp. nov. is the first appearance date for Permopsocida and roots the Acercaria tree. In addition, another specimen of Dichentomum cf. arroyo (Psocidiidae) from Carrizo Arroyo is presented and figured, confirming the presence of the genus Dichentomum near the Carboniferous-Permian boundary and linking it to the Artinskian species from Elmo in Kansas, USA.

A New Genus of Praeaulacidae (Hymenoptera: Evanioidea) from Mid-Cretaceous Kachin Amber: Insights into a Putative New Praeaulacinae Subclade.

A new praeaulacid genus and species, Azygdellitha nova gen. et sp. nov., is described and illustrated based on a male specimen from mid-Cretaceous Kachin amber from Hukawng Valley, Myanmar. This newly discovered taxon increased the diversity of praeaulacid wasps during the Cretaceous period. While this new taxon shares similarities of wing venation with most species of the subfamily Praeaulacinae, it strongly differs from that of three genera previously described from mid-Cretaceous Kachin amber: Mesevania, Paleosyncrasis, and Praegastrinus. We explore the possibility that these genera constitute a distinct tribe within the Praeaulacinae, distinguished by their wing venation. We provide illustrations and emphasize the potentially diagnostic traits supporting this classification.

Microphysiological systems inspired by leaf venation.

Nature-inspired microfluidic networks are revolutionizing microphysiological systems, allowing for the precise emulation of human physiology. This article delves into the fabrication techniques of leaf-venation-inspired (LVI) microfluidic networks and explores their transformative applications in organ-on-a-chip and tissue engineering, showcasing their pivotal role in advancing biomedical research.

Significant correlation between leaf vein length per unit area and stomatal density: evidence from Red Tip and Chinese photinias.

The vascular veins in photosynthetic leaves play an important role in transporting water and sugars throughout the plant body, and their venation pattern and vein density determine the hydraulic efficiency of the leaf. Likewise, stomatal density (SD) can influence photosynthetic gas exchange. However, the correlation between leaf vein density and SD is seldom reported. Herein, we examined 16 leaves from the hybrid Photinia × fraseri and 16 leaves from one of its parents, P. serratifolia, to explore the correlation between leaf vein density and SD. For each leaf, equidistant lamina quadrats were excised along two longitudinal transects (one along the midrib and another along the leaf margin). For each quadrat, micrographs of 1.2 mm × 0.9 mm stomatal imprints, and 2.51 mm × 1.88 mm micrographs of leaf veins were used to measure total vein area per leaf unit area (VAA) and total vein length per unit area (VLA), as indicators of leaf vein density, to determine the correlation between SD and leaf vein density. For each taxon, there was no significant correlation between SD and VAA, but there was a significant correlation between SD and VLA. The data indicate that SD is not positively correlated with VAA but positively correlated with VLA for both the hybrid and the parent species. This study indicates that future work should focus on the relationships between SD and total vein length per unit area rather than on total leaf vein area per unit area within and across species.

Effect of life cycle and venation pattern on the coordination between stomatal and vein densities of herbs.

Life cycle (annual vs perennial) and leaf venation pattern (parallel and reticular) are known to be related to water use strategies in herb species and critical adaptation to certain climatic conditions. However, the effect of these two traits and how they influence the coordination between vein density (vein length per area, VLA) and stomatal density (SD) remains unclear. In this study, we examined the leaves of 53 herb species from a subtropical botanical garden in Guangdong Province, China, including herbs with different life cycles and leaf venation patterns. We assessed 21 leaf water-related functional traits for all species, including leaf area (LA), major and minor VLA, major and minor vein diameter (VD), SD and stomatal length (SL). The results showed no significant differences in mean SD and SL between either functional group (parallel venation vs reticular venation and annual vs perennial). However, parallel vein herbs and perennial herbs displayed a significantly higher mean LA and minor VD, and lower minor VLA compared to reticular vein herbs and annual herbs, respectively. There was a linear correlation between total VLA and SD in perennial and reticular vein herbs, but this kind of correlation was not found in annual and parallel vein herbs. The major VLA and minor VD were significantly affected by the interaction between life cycle and leaf venation pattern. Our findings suggested that VLA, rather than SD, may serve as a more adaptable structure regulated by herbaceous plants to support the coordination between leaf water supply and demand in the context of different life cycles and leaf venation patterns. The results of the present study provide mechanistic understandings of functional advantages of different leaf types, which may involve in species fitness in community assembly and divergent responses to climate changes.

Dorsoventrally asymmetric expression of miR319/TCP generates dorsal-specific venation patterning in petunia corolla tube.

Vein-associated pigmentation (venation) is a type of floral coloration adopted by plants to attract pollinators. Several petunia (Petunia hybrida) lines generate dorsoventrally asymmetric venation patterning of the corolla tube, in which venation is only present in the dorsal tube. The molecular mechanism underlying this trait is unknown. Here, we demonstrate that miR319 is preferentially expressed in the dorsal corolla tube, leading to dorsoventrally asymmetric expression of its target genes. Transgenic lines overexpressing phy-miR319a generated uniform venation patterning of the corolla tube. Knockout of TCP genes targeted by miR319 promoted venation patterning in the ventral and dorsal tube, while overexpression of the miR319 target gene, PhTCP6, completely inhibited corolla tube venation patterning. In addition, miR319-targeted TCPs negatively regulated venation patterning, probably by repressing the regulator of venation patterning, AN4. Together, our data demonstrate that asymmetric expression of miR319 promotes venation patterning in the petunia dorsal tube alone by repressing the expression of its target TCP genes, which negatively regulate corolla tube venation patterning. These findings provide novel insights into how the dorsoventrally asymmetric distribution of venation patterning is established in zygomorphic flowers.

Photosynthesis of rice leaves with a parallel venation is highly tolerant to vein severing.

Vein severing in plants caused by leaf damage is common in fields where crops are cultivated. It is hypothesized that leaves with complex reticulate venation can withstand hydraulic disturbances caused by vein severing, thereby preserving leaf carbon assimilation. However, limited research focuses on vein damage of leaves with parallel venation. We studied how vein-severing affected the photosynthetic traits of rice (Oryza sativa) leaves in seconds, minutes and days, under varying water-demand conditions and differing extents of water supply disruption. Rice leaves completely lost their photosynthetic capacity within 2.5 minutes after excision. Severing the midrib resulted in reduced light-saturated photosynthetic rate (A), stomatal conductance (gsw ) and transpiration rate (E) by 2.6, 6.8 and 5.9%, respectively, already after thirty minutes. We further investigated the photosynthetic trait responses to various extents of leaf width severing, while keeping the midrib functional. Surprisingly, A, gsw and E in the downstream area of the severed leaves largely remained stable, showing minimal variation across different leaf width severing ratios. These traits declined only slightly even under increased ambient light intensity and leaf-to-air vapor pressure deficit. This sustained photosynthesis post-severing is attributed to the efficient lateral water transport. Long-term leaf damage slightly but not significantly, impacted the downstream photosynthetic traits within five days post-severing. However, a more pronounced reduction in gas exchange during leaf senescence was observed nine days after severing. These findings suggested that rice leaves can tolerate hydraulic disturbances from vein severing and maintain functionality under various conditions, which is crucial for crop yield stability. However, long-term consequences require further investigation.

Middle Jurassic insect mines on gymnosperms provide missing links to early mining evolution.

We investigated the mining mode of insect feeding, involving larval consumption of a plant's internal tissues, from the Middle Jurassic (165 million years ago) Daohugou locality of Northeastern China. Documentation of mining from the Jurassic Period is virtually unknown, and results from this time interval would address mining evolution during the temporal gap of mine-seed plant diversifications from the previous Late Triassic to the subsequent Early Cretaceous. Plant fossils were examined with standard microscopic procedures for herbivory and used the standard functional feeding group-damage-type system of categorizing damage. All fossil mines were photographed and databased. We examined 2014 plant specimens, of which 27 occurrences on 14 specimens resulted in eight, new, mine damage types (DTs) present on six genera of bennettitalean, ginkgoalean, and pinalean gymnosperms. Three conclusions emerge from this study. First, these mid-Mesozoic mines are morphologically conservative and track plant host anatomical structure rather than plant phylogeny. Second, likely insect fabricators of these mines were three basal lineages of polyphagan beetles, four basal lineages of monotrysian moths, and a basal lineage tenthredinoid sawflies. Third, the nutrition hypothesis, indicating that miners had greater access to nutritious, inner tissues of new plant lineages, best explains mine evolution during the mid-Mesozoic.

Endoplasmic Reticulum Calcium Mediates Drosophila Wing Development.

Background: The temporal dynamics of morphogen presentation impacts transcriptional responses and tissue patterning. However, the mechanisms controlling morphogen release are far from clear. We found that inwardly rectifying potassium (Irk) channels regulate endogenous transient increases in intracellular calcium and bone morphogenetic protein (BMP/Dpp) release for Drosophila wing development. Inhibition of Irk channels reduces BMP/Dpp signaling, and ultimately disrupts wing morphology. Ion channels impact development of several tissues and organisms in which BMP signaling is essential. In neurons and pancreatic beta cells, Irk channels modulate membrane potential to affect intracellular Ca++ to control secretion of neurotransmitters and insulin. Based on Irk activity in neurons, we hypothesized that electrical activity controls endoplasmic reticulum (ER) Ca++ release into the cytoplasm to regulate the release of BMP. Materials and Methods: To test this hypothesis, we reduced expression of four proteins that control ER calcium, Stromal interaction molecule 1 (Stim), Calcium release-activated calcium channel protein 1 (Orai), SarcoEndoplasmic Reticulum Calcium ATPase (SERCA), small conductance calcium-activated potassium channel (SK), and Bestrophin 2 (Best2) using RNAi and documented wing phenotypes. We use live imaging to study calcium and Dpp release within pupal wings and larval wing discs. Additionally, we employed immunohistochemistry to characterize Small Mothers Against Decapentaplegic (SMAD) phosphorylation downstream of the BMP/Dpp pathway following RNAi knockdown. Results: We found that reduced Stim and SERCA function decreases amplitude and frequency of endogenous calcium transients in the wing disc and reduced BMP/Dpp release. Conclusion: Our results suggest control of ER calcium homeostasis is required for BMP/Dpp release, and Drosophila wing development.

Cryptotermespugnus (Blattodea, Isoptera, Kalotermitidae), a new drywood termite species from the Brazilian Caatinga dry forest and key to South American Cryptotermes Banks, 1909.

A new termite species, Cryptotermespugnussp. nov., is described from northeastern Brazil. The winged imago of C.pugnus is distinguished from most congeners by the lack of arolia and the multiple branches connecting the median vein to the radial sector. The soldier is unique among South American Cryptotermes by its cuboidal head capsule and very rugose postclypeus. The new species constitutes the fourteenth Cryptotermes species on the continent for which we provide a key to soldiers.

Little bits of dragonfly history repeating exemplified by a new Pennsylvanian family.

During its 320 Myr evolution, dragon- and damselfly (Odonata) wing morphology underwent intense modifications. The resulting diversity prompted comparative analyses focusing on phylogeny. However, homoplasy proved to plague wing-related characters. Concurrently, limited benefits were obtained from considering fossil taxa, similarly impacted. Herein, we investigate two aspects particularly affected by convergence, namely the acquisition of vein-like structuring elements derived from regular cross-venation, termed conamina; and the evolution of butter knife wing shape. Conamen implementation is found to be consistently linked with vein curvature sharpening, itself generating potential breaking points. Conamina therefore likely evolved to address wing integrity issues during ever-more-demanding flight performance. Moreover, an existing conamen is likely to trigger the acquisition of further, associated conamina. As for butter knife shape, previously documented in the extinct Archizygoptera and among damselflies, we report a new, 315 Ma occurrence with the rare species Haidilaozhen cuiae gen. et sp. nov. (family Haidilaozhenidae fam. nov.), from the Xiaheyan locality (China). The repeated acquisition of butter knife-shaped wing can be related to slow speed flight and, in turn, predator avoidance. In both cases of iterated regularities, the unique 'network-and-membrane' wing design proper to insects is found to compose a strong, constraining factor.

Foliar Phenotypic Plasticity Reflects Adaptation to Environmental Variability.

Arabidopsis thaliana ecotypes adapted to native habitats with different daylengths, temperatures, and precipitation were grown experimentally under seven combinations of light intensity and leaf temperature to assess their acclimatory phenotypic plasticity in foliar structure and function. There were no differences among ecotypes when plants developed under moderate conditions of 400 µmol photons m-2 s-1 and 25 °C. However, in response to more extreme light or temperature regimes, ecotypes that evolved in habitats with pronounced differences in either the magnitude of changes in daylength or temperature or in precipitation level exhibited pronounced adjustments in photosynthesis and transpiration, as well as anatomical traits supporting these functions. Specifically, when grown under extremes of light intensity (100 versus 1000 µmol photons m-2 s-1) or temperature (8 °C versus 35 °C), ecotypes from sites with the greatest range of daylengths and temperature over the growing season exhibited the greatest differences in functional and structural features related to photosynthesis (light- and CO2-saturated capacity of oxygen evolution, leaf dry mass per area or thickness, phloem cells per minor vein, and water-use efficiency of CO2 uptake). On the other hand, the ecotype from the habitat with the lowest precipitation showed the greatest plasticity in features related to water transport and loss (vein density, ratio of water to sugar conduits in foliar minor veins, and transpiration rate). Despite these differences, common structure-function relationships existed across all ecotypes and growth conditions, with significant positive, linear correlations (i) between photosynthetic capacity (ranging from 10 to 110 µmol O2 m-2 s-1) and leaf dry mass per area (from 10 to 75 g m-2), leaf thickness (from 170 to 500 µm), and carbohydrate-export infrastructure (from 6 to 14 sieve elements per minor vein, from 2.5 to 8 µm2 cross-sectional area per sieve element, and from 16 to 82 µm2 cross-sectional area of sieve elements per minor vein); (ii) between transpiration rate (from 1 to 17 mmol H2O m-2 s-1) and water-transport infrastructure (from 3.5 to 8 tracheary elements per minor vein, from 13.5 to 28 µm2 cross-sectional area per tracheary element, and from 55 to 200 µm2 cross-sectional area of tracheary elements per minor vein); (iii) between the ratio of transpirational water loss to CO2 fixation (from 0.2 to 0.7 mol H2O to mmol-1 CO2) and the ratio of water to sugar conduits in minor veins (from 0.4 to 1.1 tracheary to sieve elements, from 4 to 6 µm2 cross-sectional area of tracheary to sieve elements, and from 2 to 6 µm2 cross-sectional area of tracheary elements to sieve elements per minor vein); (iv) between sugar conduits and sugar-loading cells; and (v) between water conducting and sugar conducting cells. Additionally, the proportion of water conduits to sugar conduits was greater for all ecotypes grown experimentally under warm-to-hot versus cold temperature. Thus, developmental acclimation to the growth environment included ecotype-dependent foliar structural and functional adjustments resulting in multiple common structural and functional relationships.

Teasing out elevational trends in infraspecific Prunus taxa: A vein analysis approach.

Using 33 specimens collected from across their range in Turkey, we demonstrate that the subspecies of Prunus microcarpa C.A.Mey react very differently to altitude. We first outline a simplified, flexible protocol for sectioning and removing the epidermis of small, difficult-to-image leaves for leaf vein studies. We then used venation analysis software to evaluate the two subspecies of this wild cherry in relation to altitude. We also found key differences in venation features between short-shoot and long-shoot leaves for each taxon. Differences include statistically significant negative correlation between vein density, and positive correlation between areole area and altitude in long-shoot leaves of Prunus microcarpa subsp. microcarpa, while its short-shoot leaves had a positive relationship between maximum areole area, and negative relationship between vein density, numbers of veins and endpoints. Meanwhile, P. microcarpa subsp. tortuosa (Boiss. & Hausskn.) Browicz recorded trends that were largely opposite of this, but beside vein thickness and areole area, were not statistically significant. This difference may be part of each taxon's overarching syndrome of anatomical and morphological adaptations to its external environment. RESEARCH HIGHLIGHTS: Features of vein density and thickness fell, while areole area and vein length rose with altitude in P. microcarpa. P. microcarpa subsp. tortuosa showed opposite trends, but reacted less strongly to altitude. Short-shoot and long-shoot have significantly different venation parameters. Using sections proportionate to leaf size is useful to compare venation of leaves that vary due to dimorphism. We discuss protocol strategies for imaging of difficult leaves for venation analyses.

Machine learning analysis of wing venation patterns accurately identifies Sarcophagidae, Calliphoridae and Muscidae fly species.

In medical, veterinary and forensic entomology, the ease and affordability of image data acquisition have resulted in whole-image analysis becoming an invaluable approach for species identification. Krawtchouk moment invariants are a classical mathematical transformation that can extract local features from an image, thus allowing subtle species-specific biological variations to be accentuated for subsequent analyses. We extracted Krawtchouk moment invariant features from binarised wing images of 759 male fly specimens from the Calliphoridae, Sarcophagidae and Muscidae families (13 species and a species variant). Subsequently, we trained the Generalized, Unbiased, Interaction Detection and Estimation random forests classifier using linear discriminants derived from these features and inferred the species identity of specimens from the test samples. Fivefold cross-validation results show a 98.56 ± 0.38% (standard error) mean identification accuracy at the family level and a 91.04 ± 1.33% mean identification accuracy at the species level. The mean F1-score of 0.89 ± 0.02 reflects good balance of precision and recall properties of the model. The present study consolidates findings from previous small pilot studies of the usefulness of wing venation patterns for inferring species identities. Thus, the stage is set for the development of a mature data analytic ecosystem for routine computer image-based identification of fly species that are of medical, veterinary and forensic importance.

The Plant Leaf: A Biomimetic Resource for Multifunctional and Economic Design.

As organs of photosynthesis, leaves are of vital importance for plants and a source of inspiration for biomimetic developments. Leaves are composed of interconnected functional elements that evolved in concert under high selective pressure, directed toward strategies for improving productivity with limited resources. In this paper, selected basic components of the leaf are described together with biomimetic examples derived from them. The epidermis (the "skin" of leaves) protects the leaf from uncontrolled desiccation and carries functional surface structures such as wax crystals and hairs. The epidermis is pierced by micropore apparatuses, stomata, which allow for regulated gas exchange. Photosynthesis takes place in the internal leaf tissue, while the venation system supplies the leaf with water and nutrients and exports the products of photosynthesis. Identifying the selective forces as well as functional limitations of the single components requires understanding the leaf as an integrated system that was shaped by evolution to maximize carbon gain from limited resource availability. These economic aspects of leaf function manifest themselves as trade-off solutions. Biomimetics is expected to benefit from a more holistic perspective on adaptive strategies and functional contexts of leaf structures.

Vein network redundancy and mechanical resistance mitigate gas exchange losses under simulated herbivory in desert plants.

Herbivory can impact gas exchange, but the causes of interspecific variation in response remain poorly understood. We aimed to determine (1) what effects does experimental herbivory damage to leaf midveins have on leaf gas exchange and, (2) whether changes in leaf gas exchange after damage was predicted by leaf mechanical or venation traits. We hypothesized that herbivory-driven impacts on leaf gas exchange would be mediated by (1a/1b) venation networks, either by more vein resistance, or possibly trading off with other structural defenses; (2a/2b) or more reticulation (resilience, providing more alternate flow pathways after damage) or less reticulation (sectoriality, preventing spread of reduced functionality after damage). We simulated herbivory by damaging the midveins of four leaves from each of nine Sonoran Desert species. We then measured the percent change in photosynthesis (ΔAn%), transpiration (ΔEt%) and stomatal conductance (Δgsw%) between treated and control leaves. We assessed the relationship of each with leaf venation traits and other mechanical traits. ΔAn% varied between +10 % and -55%, similar to ΔEt% (+27%, -54%) and Δgsw% (+36%, -53%). There was no tradeoff between venation and other structural defenses. Increased damage resilience (reduced ΔAn%, ΔEt%, Δgsw%) was marginally associated with lower force-to-tear (P < 0.05), and higher minor vein density (P < 0.10) but not major vein density or reticulation. Leaf venation networks may thus partially mitigate the response of gas exchange to herbivory and other types of vein damage through either resistance or resilience.

Closed-loop vasculature network design for bioprinting large, solid tissue scaffolds.

Vascularization is an indispensable requirement for fabricating large solid tissues and organs. The natural vasculature derived from medical imaging modalities for large tissues and organs are highly complex and convoluted. However, the present bioprinting capabilities limit the fabrication of such complex natural vascular networks. Simplified bioprinted vascular networks, on the other hand, lack the capability to sustain large solid tissues. This work proposes a generalized and adaptable numerical model to design the vasculature by utilizing the tissue/organ anatomy. Starting with processing the patient's medical images, organ structure, tissue-specific cues, and key vasculature tethers are determined. An open-source abdomen magnetic resonance image dataset was used in this work. The extracted properties and cues are then used in a mathematical model for guiding the vascular network formation comprising arterial and venous networks. Next, the generated three-dimensional networks are used to simulate the nutrient transport and consumption within the organ over time and the regions deprived of the nutrients are identified. These regions provide cues to evolve and optimize the vasculature in an iterative manner to ensure the availability of the nutrient transport throughout the bioprinted scaffolds. The mass transport of six components of cell culture media-glucose, glycine, glutamine, riboflavin, human serum albumin, and oxygen was studied within the organ with designed vasculature. As the vascular structure underwent iterations, the organ regions deprived of these key components decreased significantly highlighting the increase in structural complexity and efficacy of the designed vasculature. The numerical method presented in this work offers a valuable tool for designing vascular scaffolds to guide the cell growth and maturation of the bioprinted tissues for faster regeneration post bioprinting.