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Most of the plants using epizoochory show adaptations to this diaspore dispersal strategy by having the diaspores covered by barbs, hooks, spines or viscid outgrowths, which allow diaspores to easily attach to an animal surface. Many previous studies have been mainly focused on the dispersal distances and efficiency, or effectiveness of diverse attachment structures depending on their size, anatomy, and morphology. However, the knowledge about the mechanical properties of these structures remains rather poor. In this study, we use a combination of scanning electron microscopy, energy dispersive X-ray element analysis and nanoindentation, to examine the microstructure, biomineralization and mechanical properties of single hooks in Arctium minus, Cynoglossum officinale and Galium aparine. Both the biomineralization and mechanical properties of the hooks strongly differ in examined plant species; mechanical properties depend on the biomineralization pattern, such as the accumulation of silicon and calcium. Elastic modulus and hardness decrease in the series C. officinale G. aparine A. minus. Anisotropic mechanical properties are found between the radial and longitudinal directions in each single hook. By characterizing the mechanical properties and biomineralization of plant hooks, this paper contributes to the understanding of attachment biomechanics related to seed dispersal. The dispersal of seeds is essential for plant survival. Many of the plants that use the outside surface of animals to transport the seeds show adaptations to this dispersal strategy by having the seeds covered with hooks. Although these hooks have various sizes, morphologies and anatomical structures, all of them provide mechanical interlocking to animal surfaces. To reduce the risk of interlocking failure, the hooks are usually reinforced by mineralization. However, the relationship between mineralization, mechanical properties and specialized function of plant hooks has been largely overlooked. Here we perform a characterization study on the hooks of three plant species. Our results deepen the current understanding of the mineralization-material-function relationship in specialized hooks of plant seeds. [Display omitted] [ABSTRACT FROM AUTHOR]

Lignocellulose fillers, like cotton stalks, provide a stiffness that enhances the mechanical properties of composites. However, finding an appropriate filler loading for optimizing the mechanical performance of biocomposites remains a challenge, as there are disparities in the optimum filler loadings found in previous studies concerning the use of cotton stalk as a filler in biocomposite manufacturing. Therefore, the need for further investigations is of prime importance. Cotton-stalk-filler-reinforced high-density polyethylene (CS/HDPE) biocomposites were fabricated with different weight proportions (10-50 wt%) of the cotton stalk filler with particle size distributions 425 to 53 μm. The biocomposites were prepared using an extrusion process with a twin-screw extruder followed by compression molding in an electrically heated platen press. Results showed that the composite reinforced with 50 wt% filler gave the optimum values of tensile and flexural moduli. [ABSTRACT FROM AUTHOR]

This study describes the production of a new biobased epoxy thermoset and its use with long hemp fibres to produce high-performance composites that are totally biobased. The synthesis of BioIgenox, an epoxy resin derived from a lignin biorefinery, and its curing process have been optimised to decrease their environmental impact. The main objective of this study is to characterise the rheology and kinetics of the epoxy system with a view to optimising the composite manufacturing process. Thus, the epoxy resin/hardener system was chosen considering the constraints imposed by the implementation of composites reinforced with plant fibres. The viscosity of the chosen mixture shows the compatibility of the formulation with the traditional implementation processes of the composites. In addition, unlike BPA—a precursor of diglycidyl ether of bisphenol A (DGEBA) epoxy resin—BioIgenox and its precursor do not have endocrine disrupting activities. The neat polymer and its unidirectional hemp fibre composite are characterised using three-point bending tests. Results measured for the fully biobased epoxy polymer show a bending modulus, a bending strength, a maximum strain at failure and a Tg of, respectively, 3.1 GPa, 55 MPa, 1.82% and 120 °C. These values are slightly weaker than those of the DGEBA-based epoxy material. It was also observed that the incorporation of fibres into the fully biobased epoxy system induces a decrease in the damping peak and a shift towards higher temperatures. These results point out the effective stress transfers between the hemp fibres and the fully biobased epoxy system. The high mechanical properties and softening temperature measured in this work with a fully biobased epoxy system make this type of composite a very promising sustainable material for transport and lightweight engineering applications. [ABSTRACT FROM AUTHOR]

A novel method for the mechanical detection of wheat biomass, based on the mechanical properties of wheat plants, is proposed to enable the quick assessment of wheat biomass. The mechanical model developed for the wheat plants, based on the variable cross-section beam elastic bending theory, can be used to analyse the interactive forces between the reel and wheat plants, and predict wheat biomass based on the magnitude of the force. The influence of wheat ears on deflection was incorporated into the model. The accuracy of wheat plant deflection forces obtained using the model was confirmed through theoretical analyses, simulations and experimental measurements. Moreover, deflection tests and posture analysis were performed on the wheat plants for different locations at which the deflection forces were acting and for different plant densities. Experiments focusing on reel operation demonstrated that the deflection forces exerted by the reel rod on wheat plants could be used to predict the number of bent plants, which would subsequently help in wheat biomass estimation. The study found that the influence of the wheat ear on the deflection force significantly increased as the plant deflection increased. The deflection force was most effective at two-thirds of the height of the wheat plant. Moreover, the higher the plant density, the greater the deflection force, which was closely correlated with wheat biomass. A model was established based on the results of the linear regression performed to determine the relationship between the deflection force acting on a wheat plant and its biomass. The model with a determination coefficient of 0.9155 provided a theoretical basis for detecting the feed quantity of the combine harvester. • Analysed the interaction force between the combine harvester reel and wheat plants. • A mechanical model of wheat plant deflection was established. • The method of bending theory of elastic beam with variable cross-section is used. • Prediction of wheat biomass based on interaction force. [ABSTRACT FROM AUTHOR]

The literature shows that a circular economy can benefit some sectors such as the construction industry. This sector demands huge amounts of raw materials and produces waste when buildings and structures are demolished. This paper explores the possibility of manufacturing at industrial scale paving blocks using different types of construction and demolition wastes as aggregates, without modifying the commonly used industrial conditions. A total of four different recycled aggregates were used in this research. Both natural and recycled aggregates have been characterized. The dosages were optimized (three different formulations). Prefabricated tests have been carried out on the products manufactured in industrial plants and the evolution of mechanical properties over time has been analysed. The results obtained were analysed statistically by applying the principal component analysis (PCA) method. To ensure the security of the elements manufactured, the ionic leaching of the materials used as recycled aggregate and of the elements produced has been tested. The main implications of this research on the construction industry show that the majority of recycled aggregates used could replace 25% of the natural aggregate in manufactured precast concrete, that the properties of the aggregates should be taken into account in the different standards and that all paving blocks manufactured in this study can be considered environmentally safe (no risk of leaching) according to the Netherland Soil Quality Decree. Therefore, it is evident that it is possible to manufacture on an industrial scale paving blocks with mixed recycled aggregates, concrete and ceramic in nature, both with the fine and coarse fractions that meet the requirements of its reference standard UNE-EN 1338 and the Netherland Soil Quality Decree that evaluates environmental risks due to leaching. [ABSTRACT FROM AUTHOR]

This study sought to better understand how time of day (ToD) or turgor pressure might affect the flexural stiffness of sweet sorghum stalks and potentially regulate stalk lodging resistance. Stalk flexural stiffness measured across a 48 h period in 2019 showed a significant diurnal association with leaf water potential and stalk flexural stiffness. While the correlation between stalk flexural stiffness and this proxy for internal turgor status was statistically significant, it only accounted for roughly 2% of the overall variance in stiffness. Given that turgor status is a dynamic rather than fixed physiological variable like the cellular structure, these data suggest that internal turgor plays a small yet significant role in influencing the flexural stiffness of fully mature stalks prior to a stalk lodging event. The association was assessed at earlier developmental stages across three distinct cultivars and found not to be significant. Panicle weight and stalk basal weight, but not stalk Brix or water content, were found to be better predictors of stalk flexural stiffness than either ToD or turgor status. Observation across three cultivars and four distinct developmental stages ranging from the vegetative to the hard-dough stages suggests that stalk flexural stiffness changes significantly as a function of time. However, neither ToD nor turgor status appear to meaningfully contribute to observed variations in stalk flexural stiffness in either individual stalks or across larger populations. As turgor status was not found to meaningfully influence stalk strength or flexural stiffness at any developmental time point examined in any of the three sweet sorghum cultivars under study, turgor pressure likely offers only inconsequential contributions to the biomechanics underlying sweet sorghum stalk lodging resistance. [ABSTRACT FROM AUTHOR]

There is a great interest in replacing synthetics with natural materials to minimize global climate change and environmental pollution. This study presents a simple yet effective method to extract natural fibers such as banana, sisal, and false banana plant fibers and their mechanical properties. An effective mechanical and chemical fiber treatment to improve the mechanical behavior of the fibers is presented. The quality of the fibers and the cross-sectional area of each fiber were examined using FTIR and a Zeta 20 optical 3D microscope. Compared with the untreated fibers, the proposed treatment improved the banana, sisal, and false banana fibers by 34.78%, 22.68%, and 3.08%, respectively. The ultimate tensile strength of the treated false banana fibers was higher than those of sisal and banana fibers by 13.05% and 14.08%, respectively, and the failure strain was higher by 40% and 16.66%, respectively. On the other hand, the linear density and tenacity of false banana were slightly lower than sisal fiber but marginally higher than banana fiber. [ABSTRACT FROM AUTHOR]

Xylotrechus arvicola represents a significant insect pest impacting Vitis vinifera within the principal wine-producing territories of the Iberian Peninsula. The larvae of this species bore into grapevine wood, resulting in significant structural and biomechanical deterioration to the plant. Compressive and flexural tests were conducted to assess the mechanical properties of wood affected by X. arvicola. Compressive and flexural strength exhibited a decline with the escalation of the Total Damaged Surface Area (TDSA) of the samples, ranging from 0.31% to 0.73% in trunks and from 0.04 to 0.76% in branches, irrespective of the wood moisture content (fresh and dry). The most significant reduction in resistance occurred in affected dry trunks and branches. Notably, the deflection at break for dry samples was lower compared to fresh samples (65.00 and 97.85 mm, respectively). Moreover, the deflection at break for affected fresh samples (164.37 mm) significantly surpassed that of unaffected fresh samples (72.58 mm) and affected dry samples (37.50 mm). It is noteworthy that a higher percentage of TDSA coincided with diminished wood resistance. The percentage of fungal growth symptoms observed in affected wood samples was 66.66% for dry trunks, 75.00% for fresh branches, and 60.00% for dry branches. The damage inflicted by larvae facilitated the spread of grapevine diseases via emergence of holes created by insects upon exiting the wood and through the larval galleries connected to them. This damage also altered the mechanical properties of grapevine plants, with fresh branches exhibiting the most pronounced effects. [ABSTRACT FROM AUTHOR]

This paper presents a biomechanical study of stems of two liana species, Clematis vitalba and Vitis vinifera, investigates the mechanical performance of these two liana species and attempts to enhance the understanding of structure–function relationships. The investigation involved mechanical testing of whole plant stems, supplemented by X-ray micro-CT (X-ray computed tomography at micron voxel size) imaging and 2D microscopic images of stained cross sections of the plant stems, to derive structure–function relationships with potential for application in bioinspired composite materials. The micro-CT images were compared to the microscopic images of stained cross sections, in order to show benefits and potential drawbacks of the X-ray micro-CT method with respect to traditional methods. The high-resolution 3D imaging capacity of micro-CT is exploited to explain the structural functionality derived from the mechanical testing. A simple finite element model is developed based on the plant topology derived by the micro-CT images and proved accurate enough to model the plant’s mechanical behaviour and assess the influence of their structural differences. The two plants exhibit different to each other physical and mechanical properties (density, strength and stiffness) due to their common growth form. Anatomical cross-sectional observation and X-ray micro-CT provide complementary information. The first method allows the identification of the lignified parts, supposedly more resistant mechanically, of these structures, while the second one provides a full 3D model of the structure, admittedly less detailed but providing the spatial distribution of density contrasts supposed to be important in the mechanical properties of the plant. The proposed methodological approach opens new perspectives to better understand the mechanical behaviour of the complex structure of plants and to draw inspiration from it in structural engineering. [ABSTRACT FROM AUTHOR]

The stability of riverbank slopes is crucial in watershed ecology. The morphology and tensile strength properties of plant roots play a significant role in slope stability, which is of great importance for the ecological stability of riverbanks. The Jinsha and Yalong River basins are the largest hydropower bases in China and are in the ecologically fragile areas of the dry and hot river valleys, yet fewer studies are available on these basins. Further studies on the growth morphology and root mechanical properties of plant roots in the riparian zone at different elevations have not been reported. Therefore, we selected the dominant species of Cynodon dactylon root as the research subject, analyzed the root morphology, and conducted indoor single-root tensile tests to study its root structure and mechanical properties at various elevations. The results showed that the root morphology of Cynodon dactylon was positively correlated with elevation. Compared to low elevations (L and M), the root length increased by 57.3% and 21.47%, the root diameter increased by 24.85% and 13.92%, the root surface area increased by 93.5% and 67.37%, and the total root volume increased by 119.91% and 107.36%. As the elevation gradient increased, the flooding time decreased, leading to more developed plant roots for Cynodon dactylon. The Young's modulus ranged from 148.43 to 454.18 MPa for Ertan Cynodon dactylon roots and 131.31 to 355.53 MPa for Guanyingyan Cynodon dactylon roots. The maximum tensile strength, ultimate tensile strength, ultimate elongation, and Young's modulus of the plant root of the Cynodon dactylon showed a power function relationship with the diameter. The maximum tensile strength increased as the diameter increased, while the remaining properties decreased following a power function relationship. The maximum tensile strength, ultimate tensile strength, and Young's modulus of Cynodon dactylon were positively correlated with elevation, while the ultimate elongation was negatively correlated with elevation. The results elucidate the influence of elevation on the root morphology and mechanical properties of dominant riparian species. This provides a theoretical basis for managing and protecting riparian slopes in ecologically fragile areas. [ABSTRACT FROM AUTHOR]

Using additive manufacturing (AM) techniques like SLM and EBM provides a valuable opportunity for manufacturing biomedical devices with precise porous structures that can mitigate adverse implant complications. Gyroid sheet network structures exhibit an excellent performance among porous structures due to their bioinspired morphology and mechanical properties. This study investigates the mechanical behavior of gyroid sheet networks with different morphological parameters suitable for biomedical implants. The results show that gyroid sheet networks with 1 to 2.5 mm unit cell sizes and porosities between 50% and 85% are ideal for biomedical implants. Additionally, porous implants made of gyroid sheet networks and mentioned morphologies can be produced using SLM with a layer thickness of 30 µm, spot size of 90 µm, and powder size of around 50 µm. [ABSTRACT FROM AUTHOR]

Summary: Lignin contributes to plant mechanical properties during bending loads. Meanwhile, phytohormone auxin controls various plant biological processes. However, the mechanism of auxin's role in bending‐induced lignin biosynthesis was unclear, especially in bamboo, celebrated for its excellent deformation stability.Here, we reported that auxin response factors (ARF) 3 and ARF6 from Moso bamboo (Phyllostachys edulis (Carrière) J. Houz) directly regulate lignin biosynthesis pathway genes, and affect lignin biosynthesis in bamboo.Auxin and lignin exhibited asymmetric distribution patterns, and auxin promoted lignin biosynthesis in response to bending loads in bamboo. Employing transcriptomic and weighted gene co‐expression network analysis approach, we discovered that expression patterns of ARF3 and ARF6 strongly correlated with lignin biosynthesis genes. ARF3 and ARF6 directly bind to the promoter regions of 4‐coumarate: coenzyme A ligase (4CL3, 4CL7, and 4CL9) or caffeoyl‐CoA O‐methyltransferase (CCoAOMT2) genes, pivotal to lignin biosynthesis, and activate their expressions. Notably, the efficacy of this binding hinges on auxin levels. Alternation of the expressions of ARF3 and ARF6 substantially altered lignin accumulation in transgenic bamboo.Collectively, our study shed light on bamboo lignification genetics. Auxin signaling could directly modulate lignin biosynthesis genes to impact plant lignin content. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal (AM) fungi are ubiquitous and impactful symbionts of most land plants and can regulate essential ecological processes. AM fungi can increase the cellulose content of root cell walls and hence the root tensile strength of grass. How AM fungi can alter other essential biomechanical properties is not clear. This study aims to study the contribution of AM fungi in altering biomechanical properties by comparing mycorrhizal and non‐mycorrhizal roots. We inoculated three fungal species to vetiver grass (Chrysopogon zizanioides) for comparison. Eight root biomechanical properties (i.e., yield strain, yield stress, break strain, tensile strength, Young's modulus, plastic modulus, plastic strain, and toughness) were determined for each root using a newly developed Fortran language‐based program. Inoculating AM fungi decreased both Young's modulus and plastic modulus by 23% and 17%, respectively, versus control, although it was species‐dependent. Yield stress was not significantly affected, but tensile strength was increased by 7%–17% upon fungal symbiosis. Together with the increases in break strain by 15%–20%, mycorrhizal roots possessed a notably higher toughness than non‐mycorrhizal roots by up to 36%. Greater root cohesion of mycorrhizal roots confirmed the enhanced (1.5‐fold) factor of safety in the soil‐root system. Our findings imply that AM fungi are of significant interest in plant biomechanics and geotechnical engineering. Applying AM fungi on soil slopes has considerable potential to improve vegetation and stability of green slopes. [ABSTRACT FROM AUTHOR]

Temporally and spatially complex 3D deformation processes appear in plants in a variety of ways and are difficult to quantify in detail by classical cinematographic methods. Furthermore, many biomechanical test methods, e.g. regarding compression or tension, result in quasi-2D deformations of the tested structure, which are very time-consuming to analyze manually regarding strain fields. In materials testing, the contact-free optical 2D-or 3D-digital image correlation method (2D/3D-DIC) is common practice for similar tasks, but is still rather seldom used in the fundamental biological sciences. The present review aims to highlight the possibilities of 2D/3D-DIC for the plant sciences. The equipment, software, and preparative prerequisites are introduced in detail and advantages and disadvantages are discussed. In addition to the analysis of wood and trees, where DIC has been used since the 1990s, this is demonstrated by numerous recent approaches in the contexts of parasite-host attachment, cactus joint biomechanics, fruit peel impact resistance, and slow as well as fast movement phenomena in cones and traps of carnivorous plants. Despite some technical and preparative efforts, DIC is a very powerful tool for full-field 2D/3D displacement and strain analyses of plant structures, which is suitable for numerous in-depth research questions in the fields of plant biomechanics and morphogenesis. [ABSTRACT FROM AUTHOR]

This paper aims to explore the tensile properties of plant fiber-reinforced cementitious composites (PFRCCs). An axial tensile numerical-simulation and test study of PFRCC panels with four thicknesses was performed to analyze their tensile properties, providing a relevant basis for the engineering application of PFRCC panels. The results show that the peak load of uniaxial tensile failure of PFRCC panels with thicknesses of 8 mm, 12 mm, 15 mm and 18 mm is 424.0 N, 664.8 N, 825.0 N and 986.4 N, respectively. The bearing capacity of the panels gradually increases with the increase of the thickness. The peak tensile strain is about 0.044%, 2.93 times that of the cement matrix and the tensile strength is about 2.73 MPa. It is proved that adding plant fiber can increase the toughness of the cement matrix and increasing PFRCC panel thickness can improve its tensile bearing capacity without affecting its tensile-strength. [ABSTRACT FROM AUTHOR]

In this study, we utilized the material design library in Ansys Product 2022 R1 to analyze the impact of short plant fibers on the mechanical properties of epoxy resin. We employed the representative volume element (RVE) approach and examined different volume fractions up to 50%. The technique employed in this study was multi-scale modeling based on the finite element method (FEM) for numerical homogenization. Subsequently, we used the same software to develop a five-layer laminated composite. The samples were based on epoxy resin enriched with short plant fibers at fractions of 20% and 30%, as well as pure epoxy resin. The laminated composites were reinforced with carbon fibers. The objective of this study was to analyze the mechanical response of each sample during a tensile test, focusing on multiple parameters. The sought-after results included total deformation, directional deformation, equivalent and elastic stress (Von-mises). The samples containing epoxy resin enriched with 30% of short hemp fibers exhibited remarkable mechanical strength compared to the other samples. These results suggest that the incorporation of short hemp fibers into the matrix led to a significant improvement in the mechanical strength of the composite. [ABSTRACT FROM AUTHOR]

A study published in the Journal of Experimental Botany examines the relationship between cellulose and lignin biosynthesis in cereal plants and their mechanical strength. The researchers discovered that a transcription factor called OsTCP19 can promote cellulose biosynthesis and inhibit lignin biosynthesis at the same time, resulting in increased resistance to lodging without affecting grain yield. This finding provides a new approach to genetically engineer cereal plants to enhance their mechanical properties and improve sustainable food production. The article also discusses the significance of lodging resistance in typhoon-prone regions like East Asia and provides a list of genes associated with brittle culm mutants, which are related to cell wall properties. The study focuses on the genetic factors that contribute to the mechanical strength of rice plants. It reveals that mutations in genes involved in cell wall biosynthesis, such as CELLULOSE SYNTHASE (CESA), can impact the rigidity of the secondary cell wall. The transcription factor OsTCP19 is identified as a crucial regulator of cellulose and lignin synthesis, with its activation leading to increased cellulose content and decreased lignin content. By manipulating the expression of OsTCP19 in specific tissues, researchers were able to enhance mechanical strength without negatively affecting grain yield. However, further research is necessary to fully understand the underlying mechanisms and the effects of other genes on cell wall synthesis. [Extracted from the article]

Glutinous rice glue-plant straw-soil-fly ash brick (GPSF brick) was prepared by using plant straw, ramie fiber, soil, fly ash, glutinous rice glue as raw materials, and the influence of NaOH concentration, soaking straw time, glutinous rice glue dosage ratio, curing days, soil and fly ash mixing ratio on the mechanical properties of GPSF brick was studied by orthogonal experiments. The results show that the ratio of fly ash has a significant impact on the compressive strength of GPSF bricks. The concentration of NaOH, soil content, and fly ash content have a significant impact on the flexural strength of GPSF bricks. The optimal mix ratio for GPSF bricks is: NaOH concentration of 7%, straw soaking time of 36 hours, curing time of 21 days, glutinous rice glue, soil, and fly ash content of 100%, 125%, and 50% of plant straw mass, respectively. The compressive and flexural strength of the prepared GPSF bricks are 10.03 and 6.67 MPa, respectively. [ABSTRACT FROM AUTHOR]

Background and objectives: Soil bioengineering techniques offer multifaceted benefits and find applications across diverse landscapes. These approaches are notable for their high sustainability, adaptability to environmental changes, and effective reestablishment. While existing bioengineering studies focus largely on assessing root systems for soil stabilization, it remains pivotal to estimate key biotechnical characteristics, such as root distribution and mechanical strength, for various plant species. These insights serve as crucial inputs for developing robust soil reinforcement models. Methodology: Root system distribution and mechanical strength data are integral for accurate reinforcement estimation. In Iran, conventional methods such as profile trenching and soil core sampling were employed for destructive sampling to investigate root system distribution and density. This focused on several tree species, including Fagus orientalis Lipsky, Carpinus betulus L., Alnus glutinosa (L.) Gaertn., Acer velutinum Boiss., Quercus castaneifolia C.A.Mey., Parrotia persica (DC.) C.A.Mey., Fraxinus excelsior L., Picea abies (L.) H.Karst., Quercus brantii Lindl., Quercus libani Oliv., Haloxylon persicum Bunge ex Boiss. & Buhse, Salix alba L., Tamarix hispida Willd., and Avicennia marina (Forssk.) Vierh. The mechanical properties of root samples from various species and habitats were investigated in a laboratory setting using a universal device. A novel in-situ pullout device with a 10-kilonewton capacity was employed in Iran to measure mechanical resistance in mangrove forests. Results: Findings indicated that the mean root area ratio, a density indicator, ranged from 0.15% to 2.6%. Various factors significantly influenced root area ratio values, including species, slope gradient, health status, human intervention, stress direction, altitude, trunk diameter, age, and horizontal and vertical distances from the trunk. Mechanical resistance values were impacted by factors such as health status, pollarding, slope gradient, wind direction, season, altitude, age, and trunk diameter. Generally, higher slope gradients, trunk diameters, elevations, and ages increased root density, while diseases, pests, and pollarding treatments decreased it. Mechanical resistance values varied with factors such as season, trunk diameter, elevation, and the presence of stressors like slope and prevailing wind. In Iran, mean tensile force, tensile strength, and pullout resistance ranged between 17-145 N, 3-45 MPa, and 1.19 kN, respectively. Conclusion: Iran possesses essential data for applying classical models of soil reinforcement across various plant species. To enhance models, the use of in-situ pullout apparatus for assessing root mechanical characteristics in their natural environment is recommended. Despite the wealth of Iranian bioengineering literature, knowledge gaps persist, particularly in root architecture, distribution, and density, with a need for data on whole tree extraction and the development of allometric models for soil bioengineering applications. [ABSTRACT FROM AUTHOR]

Tendrils of climbing plants coil along their length, thus forming a striking helical spring and generating tensional forces. It is found that, for tendrils of the passion flower Passiflora caerulea, the generated force lies in the range of 6–140 mN, which is sufficient to lash the plant tightly to its substrate. Further, it is revealed that the generated force strongly correlates with the water status of the plant. Based on a combination of in situ force measurements with anatomical investigations and dehydration‐rehydration experiments on both entire tendril segments and isolated lignified tissues, a two‐phasic mechanism for spring formation is proposed. First, during the free coiling phase, the center of the tendril begins to lignify unilaterally. At this stage, both the generated tension and the stability of the form of the spring still depend on turgor pressure. The unilateral contraction of a bilayer as being the possible driving force for the tendril coiling motion is discussed. Second, in a stabilization phase, the entire center of the coiled tendril lignifies, stiffening the spring and securing its function irrespective of its hydration status. [ABSTRACT FROM AUTHOR]

Carnivorous pitcher plants (Nepenthes) are a striking example of a natural pitfall trap. The trap's slippery rim, or peristome, plays a critical role in insect capture via an aquaplaning mechanism that is well documented. While the peristome has received significant research attention, the conspicuous variation in peristome geometry across the genus remains unexplored. We examined the mechanics of prey capture using Nepenthes pitcher plants with divergent peristome geometries. Inspired by living material, we developed a mathematical model that links the peristomes' threedimensional geometries to the physics of prey capture under the laws of Newtonian mechanics. Linking form and function enables us to test hypotheses related to the function of features such as shape and ornamentation, orientation in a gravitational field, and the presence of "teeth," while analysis of the energetic costs and gains of a given geometry provides a means of inferring potential evolutionary pathways. In a separate modeling approach, we show how prey size may correlate with peristome dimensions for optimal capture. Our modeling framework provides a physical platform to understand how divergence in peristome morphology may have evolved in the genus Nepenthes in response to shifts in prey diversity, availability, and size. [ABSTRACT FROM AUTHOR]

The mechanical and chemical properties of plant cell walls greatly rely on the supramolecular assembly of cellulose fibrils. To study the local orientation of cellulose in secondary plant cell walls, diffraction limited infrared (IR) micro-spectroscopic mapping experiments were conducted at different orientation of transverse leaf section of the grass Sorghum bicolor with respect to the polarization direction of the IR radiation. Two-dimensional maps, based on polarization-sensitive absorption bands of cellulose were obtained for different polarization angles. They reveal a significant degree of anisotropy of the cellulose macromolecules as well as of other biopolymers in sclerenchyma and xylem regions of the cross section. Quantification of the signals assigned to polarization sensitive vibrational modes allowed to determine the preferential orientation of the sub-micron cellulose fibrils in single cell walls. A sample of crystalline nano-cellulose comprising both a single microcrystal as well as unordered layers of nanocrystals was used for validation of the approach. The results demonstrate that diffraction limited IR micro-spectroscopy can be used to study hierarchically structured materials with complex anisotropic behavior. [ABSTRACT FROM AUTHOR]

Riverbank erosion is an important topic in environmental research. Although several methods have been used to prevent erosion and balance ecosystems, both are still very challenging issues. We propose three different adaptation approaches to control riverbank erosion in the steppe area. The area has been affected by dramatic erosion over the past several years due to water flow and other external effects. The approaches were based on bioengineering and mechanical methods that were different in terms of the erosion rate and slope of the riverbank, the velocity and intensity of water flow, and the mechanical properties of the soil and plant species. Cost–benefit analysis (CBA) and sensitivity analysis were applied to estimate and compare the approaches. The most appropriate approaches were selected by comparing the net present value (NPV), the benefit–cost ratio, and the internal rate of return, which are the main indicators of CBA. The CBA results indicated that all the approaches had positive benefits in 2020–2030. The most economically and environmentally beneficial approach was Approach-3 (bioengineering method). A Monte Carlo sensitivity analysis demonstrated that the NPV of Approach-3 was positive in both scenarios of the pessimistic and optimistic cases of the discount rate. Monte Carlo analysis with 500 simulations was performed to obtain the future NPV. The results reveal that bioengineering methods for riverbank erosion control have higher environmental benefits and are more suitable in steppe areas. [ABSTRACT FROM AUTHOR]

Plant cell wall is a complex cross-linking network that provide mechanical support for plant cells during growth, development and adaptation to a changing environment. It has the functions of regulating plant morphology, resisting stress, transporting water, etc. In addition, most of the biomass accumulated by plant photosynthesis is stored in the cell wall. Therefore, it is of great significance to study the composition and structure of the cell wall for better utilization of plant energy. The nano-microstructure of plant cell wall is one of the frontier hotspots in plant research. With the development of new imaging technologies, a large number of studies had been conducted on the composition and structure of the cell wall. In this work, we summarized the composition, structure, imaging technology and mechanical property of the plant cell wall, in order to provide new ideas for studying plant cell wall [ABSTRACT FROM AUTHOR]

[Display omitted] • Pectin metabolism patterns in lignified loquat fruit were different from other fruits. • Low-methylesterified HG accumulated in cell walls of loquat fruit during cold storage. • Low-methylesterified HG formed egg-box structure with Ca2+ in lignified loquat fruit. • LTC treatment inhibited the increase of low-methylesterified HG and egg-box structure. • Accumulation of pectin-involved egg-box structure was related to firmness increase. Postharvest textural changes in fruit are mainly divided into softening and lignification. Loquat fruit could have severe lignification with increased firmness during postharvest storage. Pectin is mainly associated with the postharvest softening of fruit, but some studies also found that pectin could be involved in strengthening the mechanical properties of the plant. This study focused on characterizing the dynamics of pectin and its complexation in the cell wall of lignified loquat fruit during postharvest storage, and how these changes could influence fruit firmness. The homogalacturonan (HG) pectin in the cell wall of loquat fruit was identified using monoclonal antibodies. An oligogalacturonide (OG) probe was used to label the egg-box structure formed by Ca2+ cross-linking with low-methylesterified HG. An exogenous injection was used to verify the role of egg-box structures in the firmness increase in loquat fruit. The JIM5 antibody revealed that low-methylesterified HG accumulated in the tricellular junctions and middle lamella of loquat fruit that had severe lignification symptoms. The pectin methylesterase (PME) activity increased during the early stages of storage at 0 °C, and the calcium-pectate content and flesh firmness constantly increased during storage. The OG probe demonstrated the accumulation of egg-box structures at the cellular level. The exogenous injection of PME and Ca2+ into the loquat flesh led to an increase in firmness with more low-methylesterified HG and egg-box structure signals. PME-mediated demethylesterification generated large amounts of low-methylesterified HG in the cell wall. This low-methylesterified HG further cross-linked with Ca2+ to form egg-box structures. The pectin-involved complexations then contributed to the increased firmness in loquat fruit. Overall, besides being involved in fruit softening, pectin could also be involved in strengthening the mechanical properties of postharvest fruit. This study provides new ideas for obtaining a better texture of postharvest loquat fruits based on pectin regulation. [ABSTRACT FROM AUTHOR]

Sorghum is a versatile plant with various parts that can be utilized. However, information on the physical and mechanical properties of the sorghum plant is crucial for designing agricultural machinery for primary handling processes such as threshing and chopping. This study aimed to determine the technical characteristics of sorghum plants (Bioguma variety) including the physical and mechanical properties of the stems, leaves, panicles and seeds to design a configuration system concept for threshing and chopping machines capable of processing sorghum plants with high moisture content immediately after harvesting. The study used a descriptive method and included samples of sorghum plants randomly taken from fields in Majalengka and Bogor, Indonesia. The physical and mechanical properties were measured using several replications, ranging from 3 to 30 depending on the parameter. The sorghum plants were harvested at at ages 80, 90 and 108 days after transplanting (DAT). It was found that the moisture content of sorghum stem and seeds decreased with the increase of plant ages where stem ranged between 84.18-79.81 %wb and seeds ranged between 51.7-29.4 %wb. The result revealed that planting ages influenced its properties including stem properties and seed properties. Longer DAT increased the stem hardness from 290.64 ± 29.41 to 350.00 ± 0.81 N and seed hardness from 8.2 ± 1.7 to 44.9 ± 5.4 N but decreased the tensile force of seed form panicles from 16.7 + 3.2 to 6.0 ± 0.8 N. The data on stem strength and seed hardness provide important considerations for the development of several equipment for sorghum processing. The findings of this study can serve as a basis for designing effective and efficient threshing and chopping machines for sorghum plants at high moisture content. [ABSTRACT FROM AUTHOR]

Their results involve the CLV3 peptide as well as CLV1 and CLV2/CRN receptors that promote auxin-dependent primordium initiation, likely by inducing I YUCCA i auxin biosynthesis genes. Keywords: auxin; morphogenesis; plant development; regeneration; single-cell transcriptomics EN auxin morphogenesis plant development regeneration single-cell transcriptomics 1729 1731 3 11/06/23 20231201 NES 231201 After having spent over 2 years mostly online due to the COVID-19 outbreak, the Mechanism of Plant Development Conference 2022 renewed our ability to meet and engage in-person with fantastic scientists from across the field of plant development. Auxin, morphogenesis, plant development, regeneration, single-cell transcriptomics. [Extracted from the article]

In this topic, 12 genes of serine hydroxy-methyltransferase ( I SHMT i ), 227 genes of basic leucine zipper ( I bZIP i ) and 10 genes of catalases ( I CATs i ) were identified in wheat, and the members with potentially regulating plant growth and the responses to various abiotic stresses were explored in several studies [[1], [3]]. The functional relationship of several metabolic genes (i.e., chalcone synthase gene, I PdCHS i , chalcone isomerase gene, I PdCHI i and chalcone2'-glucosyltransferases gene, I PdTHC2'GT i ) with ISP biosynthesis revealed that I PdTHC2'GT i may likely be a critical target for breeding yellow peony tree varieties [[19]]. 35742894 48 Zhang L., Miao L., He J., Li H., Li M. The Transcriptome and Metabolome Reveal the Potential Mechanism of Lodging Resistance in Intergeneric Hybrids between Brassica napus and Capsella bursa-pastoris. [Extracted from the article]

Natural fibers were used to modify alkali-activated fly-ash mortars. Arundo donax is a common, fast-growing, widespread plant with interesting mechanical properties. Short fibers of different lengths (from 5 to 15 mm) were added at a 3 wt% ratio to the binder amount to the alkali-activated fly-ash matrix. The possible effects on the fresh and cured properties of the mortars deriving from the different lengths of the reinforcing phase were investigated. The flexural strength of the mortars increased by up to 30% at the longest fiber dimensions, while the compressive strength remained almost unchanged in all of the compositions. The dimensional stability was increased slightly upon the addition of the fibers, depending on the fiber length, while the porosity of the mortars was reduced. Moreover, contrary to what was expected, the water permeability was not increased by the fibers' addition, irrespective of their length. The durability of the obtained mortars was tested through freeze–thaw and thermo-hygrometric cycles. The results obtained so far underline a fair resistance to the changes in temperature and moisture and a better resistance to the freeze–thaw stresses of the reinforced mortars. [ABSTRACT FROM AUTHOR]

Crop mechanical properties are widely used in the studies of crop lodging resistance, machine-crop-soil interaction system and crop cultivation. Theoretical support can greatly contribute to the lodging resistance varieties for the quality of machine operation and cultivation. The mechanical properties of crops are also closely related to their morphological structure, anatomical characteristics, and chemical compounds. This review was focused mainly on the mechanical properties associated with the volume fraction of the main compound components (including cellulose, hemicelluloses, lignin, and pectin) in each cell wall layer, the thickness, and the microfibrillar angle. The structure models were also established for the cell wall layer. The elastic mechanics model of each cell wall layer was then constructed using the Halpin-Tsai equation. The elastic model of the cell wall was built using the classical laminate theory and the boundary conditions of each wall layer. The finite Element Method (FEM) was used to solve those mechanical models. The mechanical properties of the cell and cell wall were characterized by the Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), and Atomic Force Microscope (AFM), and Confocal Raman Microscope (CRM). A systematic investigation was made to clarify the influences of cell morphology, structure, size, arrangement, and density on the mechanical properties of tissues. The cell geometry model reconstruction of tissues was performed on the Voronoi Diagram, Skeleton, Ellipse Fitting, and High-Resolution X-ray microtomography. The mechanical models of tissue were represented by the linear elastic, nonlinear rheological and twodimensional honeycomb system mechanical model using the finite or discrete element method (FEM or DEM). The mechanical properties of tissue were verified by the micro-scale tension, compression and shear tests. Previous research was found to determine the influence of tissue distribution and arrangement on the mechanical properties of organs. Furthermore, the geometric structure model was also built, according to the characteristics of external morphology and internal microstructure of the organ. The mechanical model of organs was constructed to assign the mechanical property parameters of tissues, and then for the setting load and constraint conditions. FEM was then used to solve the mechanical models. Much effort also focused on the influences of the number, spatial distribution, and arrangement of various organs on the mechanical properties of plants. The plant geometric structure model included the geometric model of each organ, the spatial position, and the posture of each organ on the plant. The mechanical model of the plant was built to assign the mechanical property parameters to each organ in the plant geometric structure model, and then set the connection, constraint mode, and boundary conditions on each organ. The FEM was also used to analyze the mechanical properties of the plant under a specific load. As such, the concept of crop multiscale mechanics was summarized during this time. Namely, the mechanical properties of corps were analyzed to take the cell wall layer, cell wall, cell, tissue, and organ as the basic components, thus building the geometric structure and mechanical models of the cell wall, cell, tissue, organ, and plant, together with the research contents of their structure mechanics. The concept of crop multi-scale mechanics was proposed to systematically summarize the research contents. The findings were also helpful to the formation of crop multi-scale mechanics theory, the establishment of database and the development of analysis software. [ABSTRACT FROM AUTHOR]

Background: Soil compaction can occur due to the intensity of tractor traffic in the tillage process. The objective of this study was to determine the changes in physical, mechanical properties of the soil and plant growth that occurred due to tractor traffic and how it would affect if the addition of organic matter (compost) was added to the soil. Methods: The experimental work was conducted at the Sugarcane Plantation of PTPN II Klumpang at an initial soil moisture content of 24.69% and a bulk density of 1.08 gr/cm3 with compost and no compost then the land is traversed by the tractor with 2,4 and 6 passes. Result: The results of indicate that the tractor trajectory and the addition of compost have a significant effect on soil compaction. The highest values for water content, bulk density, particle density and penetration resistance were obtained at 6 times tractor traffic with soil without compost sowing respectively 35.36%, 1.31 gr/cm3, 1.87 gr/cm3, 9.61 kgf/cm2, while in soil with compost, the values obtained were 33.62%, 1.23 gr/cm3, 1.82 gr/cm3, 9.04 kgf/cm2, respectively. These findings indicated that the application of compost can reduce the level of soil density so that plant growth becomes better and more even rate of plant growth is obtained than without compost. [ABSTRACT FROM AUTHOR]

Plant fibers are one of the most promising calcium silicate board (CSB) reinforcement materials because of their many sources, suitable sizes, high tensile strengths, and natural renewable properties. In this study, an applicable plant fiber selection method for reinforcing CSBs was established. The morphology, components, and mechanical properties of different brands of plant fibers were analyzed for factor screening. Based on the wet processes of CSBs, the effects of plant fiber additions on the mechanical properties of CSBs were studied, and the optimum addition amount of plant fiber was determined to be 8 wt.%. Through multiple linear regression analysis of the physical and chemical properties of plant fibers and the mechanical properties of CSBs, a plant fiber strengthening index (Fsi) and toughening index (Fti) of CSBs were formulated as a plant fiber applicability index. The fitted R2 values of the plant fiber strengthening index and toughening index were 0.88 and 0.71, respectively, showing good correlation. The validity of the plant fiber applicability index in evaluating the fiber reinforcement potential was verified by experiments. The results provided a significant method for the prediction of plant fibers' reinforcement potential and the selection of plant fibers for CSB reinforcement. [ABSTRACT FROM AUTHOR]

Tendon-to-bone repairs often fail when sutures pull through tendon, like a wire through cheese. Repair strength is maximized when loads are balanced equally among all sutures, relative to the pullout resistance of the tendon and the strength of the sutures. This problem of balancing loads across multiple, discrete attachment sites has been solved in nature by hitchhiker plants that proliferate by adhering relatively stiff fruit to relatively soft fur and fabrics through arrays of hooks. We, therefore, studied the fruits of such a plant, Harpagonella palmeri, and developed a discrete shear lag analysis of the force distributions in H. palmeri's linear arrays of long, slender hooks of varied lengths and spacing. Results suggested that strategies were used by the plant to distribute loads, including variations in the spacing and stiffnesses of hooks that serve to equalize forces over attachment sites. When applying these models to suturing schemes for surgical reattachment of tendon to bone, results suggested that strategies exhibited by H. palmeri show promise for balancing forces over sutures, potentially doubling repair strength relative to what could be achieved with a uniform suture distribution. Results suggest a potential pathway for strengthening surgical repairs, and more broadly for optimizing fasteners for bi-material attachment. [ABSTRACT FROM AUTHOR]

Silica nanoparticles were reported that can improve the fire safety and mechanical properties of polymers simultaneously due to excellent rigidity and physical barrier effect. However, its efficiency was limited by the agglomeration in polymers due to their high specific surface energy. Silica@ polydopamine (SiO2@PDA) was prepared by a facile self-polymerization method to comprehensively improve fire safety, thermal stability, and mechanical properties of plant fiber-reinforced polymer (PFRP) composites. The results of micro-morphology confirmed that the SiO2@PDA nanoparticles exhibit better dispersion state in epoxy matrix. The introduction of SiO2@PDA further increased the thermal decomposition temperature and the yield of graphitized char residue of PFRP composites compared to pure silica nanoparticles. And the fire safety of composites including limiting oxygen index, heat parameters, smoke parameters and mass loss rate was improved effectively. Particularly, the time to ignition of composites was delayed by 30 s, which was beneficial for individuality escape and rescue. Meanwhile, the improvement of storage modulus suggested the SiO2@PDA enhanced the mechanical properties of the PFRP composites. And it was proved that PDA can improve the graphitization degree of char layer and release inert gas including NH3 and CO2 during combustion. The effectiveness of non-toxic PDA in enhancing the quality of char layer and optimizing the interface to improve the dispersion state of nanoparticles appeared promising potential in the field of manufacturing fire-safe polymer-matrix composites. [ABSTRACT FROM AUTHOR]

In order to investigate the feasibility of developing a new material to substitute disposable plastics to reduce environmental pollution, four kinds of plant leaf fibers (lotus leaf, reed leaf, bamboo leaf and ginkgo leaf) were selected to combined with agar to prepare fully degradable composites (referred as LAC, RAC, BAC and GAC, respectively). The chemical composition, functional groups and thermal properties of plant leaf fibers were analyzed. The morphology of the tensile cross section of the composites was observed, and the mechanical properties, moisture absorption profile and thermal conductivity of the composites were studied. The cellulose content in the plant leaf fibers was relatively high, among which the reed leaf fiber had the highest one, which was 27.75%. The thermal stability of lotus, reed and ginkgo leaf fiber was close, while that of bamboo leaf fiber was poor. Among the four kinds of plant leaf fiber composites, reed leaf fiber/agar composite has the best mechanical properties, and its tensile, flexural and impact strength were 1.81 MPa, 6.59 MPa and 5.09 kJ/m², respectively. The BAC had a poor internal combination with many internal defects leading to its poor mechanical properties. [ABSTRACT FROM AUTHOR]

Background: While poplar (Populus spp.) is an important source of raw materials for the wood processing sector in many regions of the world, in New Zealand it has a reputation for producing poor grade recoveries of sawn timber that is unsuitable for structural applications. However, the 'Kawa' poplar clone (Populus deltoides Marshall x P. yunnanensis Dode), which has relatively high wood density, could yield structural timber. This, along with evidence demonstrating building code compliance, would improve utilisation options for this species in New Zealand. Methods: Sawn timber conversion and grade recovery were quantified for a 28-year-old pruned stand of 'Kawa' poplar grown in Northland, New Zealand. A sample of 90 mm x 45 mm structural boards were tested to determine their mechanical properties and the resulting strength class. Boron preservative retention and penetration were measured to determine whether timber could be treated to the level required under New Zealand's building standards. Density, modulus of elasticity and modulus of rupture were assessed on small defect-free specimens taken from different radial and vertical positions within trees to determine intra-stem and inter-stem variation in these properties. Results: The overall conversion of logs to sawn timber was 53%, with approximately 94% of this recovery consisting of graded timber. The most common sources of downgrade were knots, pruning wounds, and end-splits. Approximately 70% of the sawn boards were graded as clears, with smaller recoveries of cladding and structural boards. The average length of clear section was approximately 2.5 m. Mechanical testing of structural boards demonstrated that they have characteristic values sufficient to meet the requirements for the SG10 strength class. Preservative treatment achieved the H1.2 specification. Density, modulus of elasticity and modulus of rupture were all higher in specimens cut from the outside of the log compared with those taken from near the pith at all heights up the stem. Conclusions: Mechanical properties and boron treatment results indicate suitability for structural applications in accordance with New Zealand's building code. 'Kawa' poplar also produced high grade recoveries suggesting potential for commercial sawn timber production, especially for structural appearance products. [ABSTRACT FROM AUTHOR]

Plants and herbivorous insects, as well as their natural enemies such as predatory and parasitoid insects, are united by intricate relationships. Additionally, insect mouthpart mechanics are adapted to certain mechanical properties of the plant surface, which, in combination, may influence insect-plant interactions. The chemical basis of insect-plant interactions has been established, and in many examples the feeding and oviposition site selection of phytophagous insects are dependent on plant secondary metabolites. [Extracted from the article]

The article discusses a recent paper published in Development that explores the role of the CLAVATA3 (CLV3) gene in regulating stem cell maintenance in plants. The researchers interviewed in the article, Léa Rambaud-Lavigne, Namrata Gundiah, Arezki Boudaoud, and Pradeep Das, discuss their respective labs' research goals, which include investigating plant morphogenesis, cell mechanics, and gene expression patterns. The paper's key findings reveal that the cells in mutant apices, where the CLV3 gene is deleted, do not adhere to typical stem cell characteristics. The researchers also discuss their motivations for submitting the paper to Development and their future research plans. [Extracted from the article]

In order to advance the development of bio-composite materials, studies are being carried out on the potentials of using reinforcements from a natural origin in polymer matrixes. In this study, thermal conductivity, water absorption, and mechanical properties of calcined eggshell particles-treated sisal fiber hybrid reinforced epoxy composites were investigated in order to ascertain its potentials for use as structural materials. Calcined eggshell particulate (CEP) was obtained from chicken eggshell while treated sisal fibers (TSF) were obtained from the Agave sisalana plant. Both processed reinforcements were incorporated into an epoxy matrix using the hand lay-up method for the development of the bio-composites. Thermal, water absorption and mechanical behavior tests were carried out on the developed composites and the control sample. Analysis of the results showed that the presence of the bio-fillers in the epoxy matrix enhances the insulating, resistance to water uptake, and mechanical properties of the composites compared to the unreinforced epoxy matrix. It was concluded that these bio-fillers could be effectively used as reinforcements in a polymer matrix for the production of green composites. [ABSTRACT FROM AUTHOR]

The biopolymer lignin is deposited in the cell walls of vascular cells and is essential for long-distance water conduction and structural support in plants. Different vascular cell types contain distinct and conserved lignin chemistries, each with specific aromatic and aliphatic substitutions. Yet, the biological role of this conserved and specific lignin chemistry in each cell type remains unclear. Here, we investigated the roles of this lignin biochemical specificity for cellular functions by producing single cell analyses for three cell morphotypes of tracheary elements, which all allow sap conduction but differ in their morphology. We determined that specific lignin chemistries accumulate in each cell type. Moreover, lignin accumulated dynamically, increasing in quantity and changing in composition, to alter the cell wall biomechanics during cell maturation. For similar aromatic substitutions, residues with alcohol aliphatic functions increased stiffness whereas aldehydes increased flexibility of the cell wall. Modifying this lignin biochemical specificity and the sequence of its formation impaired the cell wall biomechanics of each morphotype and consequently hindered sap conduction and drought recovery. Together, our results demonstrate that each sap-conducting vascular cell type distinctly controls their lignin biochemistry to adjust their biomechanics and hydraulic properties to face developmental and environmental constraints. [ABSTRACT FROM AUTHOR]

High-tech sensors, energy harvesters, and robots are increasingly being developed for operation on plant leaves. This introduces an extra load which the leaf must withstand, often under further dynamic forces like wind. Here, we took the example of mechanical energy harvesters that consist of flat artificial "leaves" fixed on the petioles of N. oleander, converting wind energy into electricity. We developed a combined experimental and computational approach to describe the static and dynamic mechanics of the natural and artificial leaves individually and join them together in the typical energy harvesting configuration. The model, in which the leaves are torsional springs with flexible petioles and rigid lamina deforming under the effect of gravity and wind, enables us to design the artificial device in terms of weight, flexibility, and dimensions based on the mechanical properties of the plant leaf. Moreover, it predicts the dynamic motions of the leaf--artificial leaf combination, causing the mechanical-to-electrical energy conversion at a given wind speed. The computational results were validated in dynamic experiments measuring the electrical output of the plant-hybrid energy harvester. Our approach enables us to design the artificial structure for damage-safe operation on leaves (avoiding overloading caused by the interaction between leaves and/or by the wind) and suggests how to improve the combined leaf oscillations affecting the energy harvesting performance. We furthermore discuss how the mathematical model could be extended in future works. In summary, this is a first approach to improve the adaptation of artificial devices to plants, advance their performance, and to counteract damage by mathematical modelling in the device design phase. [ABSTRACT FROM AUTHOR]

Both geopolymer and plant fiber (PF) meet the requirements of sustainable development. Geopolymers have the advantages of simple preparation process, conservation and environmental protection, high early strength, wide source of raw materials, and low cost. They have broad application prospects and are considered as the most potential cementitious materials to replace cement. However, due to the ceramic-like shape and brittleness of geopolymers, their flexural strength and tensile strength are poor, and they are sensitive to microcracks. In order to solve the brittleness problem of geopolymers, the toughness of composites can be improved by adding fibers. Adding fibers to geopolymers can limit the growth of cracks and enhance the ductility, toughness and tensile strength of geopolymers. PF is a good natural polymer material, with the advantages of low density, high aspect ratio. It is not only cheap, easy to obtain, abundant sources, but also can be repeatedly processed and biodegradable. PF has high strength and low hardness, which can improve the toughness of composites. Nowadays, the research and engineering application of plant fiber-reinforced geopolymers (PFRGs) are more and more extensive. In this paper, the recent studies on mechanical properties of PFRGs were reviewed. The characteristics of plant fibers and the composition, structure and properties of geopolymers were reviewed. The compatibility of geopolymer material and plant fiber and the degradation of fiber in the substrate were analyzed. From the perspective of the effect of plant fibers on the compression, tensile and bending properties of geopolymer, the reinforcing mechanism of plant fibers on geopolymer was analyzed. Meanwhile, the effect of PF pretreatment on the mechanical properties of the PFRGs was analyzed. Through the comprehensive analysis of PFFRGs, the limitations and recommendations of PFFRG are put forward. [ABSTRACT FROM AUTHOR]

The study investigated the effect of ozone treatment applied to Kalanchoe daigremontiana plants on the contents of selected phytochemicals and on markers of oxidative stress in the leaves. For this purpose, alligator plants were exposed to the gaseous ozone applied at a rate of 5 and 10 ppm for 1, 5, and 10 min. Subsequently, tests were performed to assess the ozone-treated plants for the ability to produce reactive oxygen species (ROS), and for the activation of superoxide dismutase (SOD) and catalase (CAT), i.e., enzymes responsible for the decomposition of ROS. Measurements were also carried out to determine antioxidant potential, total contents of polyphenols, and vitamin C in plants as well as their mechanical properties. The findings show that the use of controlled conditions of ozone treatment (10 ppm; 1 min) resulted in increased contents of selected bioactive compounds (enhancement of total polyphenols 79%, enhancement of antioxidant potential ABTS 55.6% and DPPH 65.8%) in the ozone-treated raw material, with no phytotoxic effects of the process observed. It was shown that a short duration of ozone treatment is related to the increased activity of SOD (max 44%) and CAT (max 18.8%), which contributes to the lower production of ROS in cells of Kalanchoe daigremontiana. [ABSTRACT FROM AUTHOR]

Endocytic trafficking underlies processes essential for plant growth and development, including the perception of and response to abiotic and extracellular stimuli, post‐Golgi and exocytic trafficking, and cytokinesis. Protein adaptors and regulatory factors of clathrin‐mediated endocytosis that contribute to the formation of endocytic clathrin‐coated vesicles are evolutionarily conserved. Yet, work of the last ten years has identified differences between the endocytic mechanisms of plants and Opisthokonts involving the endocytic adaptor TPLATE complex, the requirement of actin during CME, and the function of clathrin‐independent endocytosis in the uptake of plant‐specific plasma membrane proteins. Here, we review clathrin‐mediated and ‐independent pathways in plants and describe recent advances enabled by new proteomic and imaging methods, and conditional perturbation of endocytosis. In addition, we summarize the formation and trafficking of clathrin‐coated vesicles based on temporal and structural data garnered from high‐resolution quantitative imaging studies. Finally, new information about the cross‐talk between endocytosis and other endomembrane trafficking pathways and organelles will also be discussed. [ABSTRACT FROM AUTHOR]

Fast snapping in the carnivorous Venus flytrap (Dionaea muscipula) involves trap lobe bending and abrupt curvature inversion (snap‐buckling), but how do these traps reopen? Here, the trap reopening mechanics in two different D. muscipula clones, producing normal‐sized (N traps, max. ≈3 cm in length) and large traps (L traps, max. ≈4.5 cm in length) are investigated. Time‐lapse experiments reveal that both N and L traps can reopen by smooth and continuous outward lobe bending, but only L traps can undergo smooth bending followed by a much faster snap‐through of the lobes. Additionally, L traps can reopen asynchronously, with one of the lobes moving before the other. This study challenges the current consensus on trap reopening, which describes it as a slow, smooth process driven by hydraulics and cell growth and/or expansion. Based on the results gained via three‐dimensional digital image correlation (3D‐DIC), morphological and mechanical investigations, the differences in trap reopening are proposed to stem from a combination of size and slenderness of individual traps. This study elucidates trap reopening processes in the (in)famous Dionaea snap traps – unique shape‐shifting structures of great interest for plant biomechanics, functional morphology, and applications in biomimetics, i.e., soft robotics. [ABSTRACT FROM AUTHOR]

The most important reason why natural fibers are not sufficiently involved in applications is the large scattering of their properties. In addition, it is very difficult to find one kind of natural fiber which has perfect mechanical properties like synthetic fibers. Here, we aimed to find solutions by developing a hybrid composite according to the expectations in the field of application. With this method, desired mechanical properties can be designed, and the weak properties can be improved. To be able to examine this method, we used two different fibers which have different mechanical characteristics. The mechanical properties were measured with three-point bending and impact resistance tests. According to the results, the flexural strength of the jute-reinforced composites (JC) has been improved by 44–71% using luffa fiber hybridization method. On the other hand, it has been observed that the impact resistance of the same specimens of JC has been improved by 51–83%. These results revealed that it is possible to improve the mechanical properties of the composites with hybridization. In conclusion, our study shows that bio-composites can be designed according to the requirement of the application. Hence, the application areas of bio-composites can be widened with increased usage rates. [ABSTRACT FROM AUTHOR]

Because tissues within the organ differ in cell size and cell wall stiffness, this pressurization leads to different stresses in different organ portions. Bold et al. [[12]] performed detailed anatomical analyses and comprehensive mechanical tests at the scales of cell (single fiber), tissue, and tissue complex (whole bark). Also, in the case of plant organs, the prestress, referred to as tissue stress or tensegrity at the organ scale, improves their mechanical performance [[2]]. Plants are multicellular organisms of a unique structure because their tissues consist of two interwoven networks: a network of interconnected protoplasts that is embedded in a network of tightly joined cell walls. [Extracted from the article]

The aim of this study is to investigate the effect of municipal solid waste incineration bottom ash from a cogeneration plant on the physical and mechanical properties and durability of cement concrete. Part of the cement in concrete mixtures tested was replaced with 0%, 3%, 6%, 9%, and 12% by weight of municipal solid waste incineration bottom ash. Concrete modified with 6% of bottom ash had a higher density (2323 kg/m3), compressive strength at 28 days (36.1 MPa), ultrasonic pulse velocity (3980 m/s), and lower water absorption rate (3.93%). The tests revealed that frost resistance, determined in all-sided testing directions, of concrete modified with 6%, 9%, and 12% of bottom ash added by weight of cement corresponds to strength grade F100. Such concrete can be used in construction works. [ABSTRACT FROM AUTHOR]

Introduction: In the Mechanical Plant “Fabric Aguilar Noriega”, the manufacture of parts as a result of casting has decreased notably in recent years, although it is still one of the main forms of production. In the molding process, mixtures are used that vary in their properties and composition, according to the intended use, such as MC-3, MCE-4 (Large steel pieces), MR-1 (single mixture), this last mixture is composed of bentonite and molasses, as binders, together with the silica sand. Objective: To perform a characterization of a unique type molding mixture with the use of refractory additives, products of the grinding of chamotte bricks, discarded in the repairs of the company's furnaces. Materials and Methods: In order to carry out this work, a design of experiment was carried out, taking into account the main materials, silica sand and bentonite, and substituting molasses for the refractory element. Results and Discussion: The results of the experiments showed that the mixture with the best properties is the one with a refractory-bentonite ratio (1:9). A real test was carried out with this mixture, using an aluminum alloy, where an excellent result was observed. Conclusions: The main conclusion is that from the results obtained, it can be stated as a fact that molasses can be substituted by refractory elements for certain types of alloys, in this case aluminum. [ABSTRACT FROM AUTHOR]

L-SAC cement soil was prepared with low alkalinity sulphoaluminate cement (L-SAC), and its mechanical properties and vegetation properties were studied. The test results show that the compressive strength, cohesion and erosion resistance of L-SAC cement soil will be improved by different degrees with the increase of L-SAC mixing proportion. By measuring the plant height of eight high alkali resistant plants in L-SAC cement soil prepared with 8% L-SAC, the results show that the L-SAC cement soil prepared with 8% L-SAC has good vegetation performance. The five species including Bermudagrass can be used as the pioneer plants of L-SAC planting cement soil. By analyzing the physical and mechanical properties and planting properties of L-SAC planting cement soil mixed with additives, three modifiers including Runzhi ecological modifier are determined. [ABSTRACT FROM AUTHOR]