The increase in the concentration of greenhouse gases of anthropogenic origin, especially carbon dioxide, concerns different spheres of society. In light of this, efforts, such as carbon capture and utilization, are being made to ensure the temperature addition limit of 1.5°C is not exceeded by 2100. Within this scenario, the construction sector presents itself critically, especially due to cement, which accounts for between 7% and 8% of global carbon dioxide emissions. It is known that during the life cycle of cementitious materials, a natural carbonation process occurs, where CO2 is reincorporated into the cementitious matrix. Thus, this study sought to investigate the biological processes related to carbon capture and utilization for structural consolidation in order to assimilate the strategies applied in nature. It also sought to assess the viability of replication in artificial processes as a mechanism for enhancing the carbonation that occurs in the life cycle of cementitious materials, incorporating environmental intelligence to address environmental and urban challenges. A literature review confirmed the potential benefit of carbon capture, utilization, and storage inspired by the biomineralization process, and this can be observed in the marine ecosystem. Additionally, the relevance of oceans as a source of knowledge for the development of new solutions is highlighted. As an additional contribution of the study, the detailed process of biomimetic thinking presented throughout the discussion is highlighted, emphasizing the multidisciplinary scope necessary to ensure the understanding of design strategies.

Regenerative medicine is a promising field that aims to reconstruct diseased or defective tissues. The primary goal of tissue engineering is to develop systems that can mimic the natural ECM using both natural and synthetic materials, and nanofibers are an excellent tool for this purpose. Electrospinning is a method for fabricating fibrous structures that offer great potential for the creation of biomimetic systems. Nanofibers mimic key aspects of the native ECM, making them a promising approach to improving tissue efficiency. Collagen and other extracellular matrix fibrous proteins with diameters in the nanometer or sub-micrometer range are abundant in the body, and porous nanofibers with high surface area and porosity can be used to mimic the ECM and promote tissue regeneration. Advanced bioactive dressings can be made using electrospinning. These dressings are popular due to their flexibility, ability to mimic the structure of the extracellular matrix (ECM), and ability to support the wound healing process. This emerging technology has the potential to create effective wound dressings and care products. There is a great focus on the development of suitable fibrous bioactive dressing materials for the treatment of chronic and acute wounds. Various composite fibers made from natural and synthetic polymers are used to create these dressings. Additionally, medicinal and biological agents are incorporated into the structure of fibrous dressings to control pain, prevent infection, and promote tissue repair and regeneration. This ensures that the wound-healing process progresses smoothly without any possible complications. As innovation progresses, more complex systems are developed in a controlled manner.

This study delves into the realms of Parametric Design and Auxetic Structures, focusing on structures exhibiting unconventional behavior, i.e., those that have a mechanical function inverse to the conventional one and expand when subjected to an external force (giving them anti-rubber properties due to their negative Poisson's ratio). It explores the theoretical underpinnings, historical evolution, and diverse applications of these structures across architecture, engineering, biology, design, and art. Through the lens of three case studies, the study showcases the utilization of Rhinoceros and Grasshopper software used for designing grids based on auxetic structures, offering versatility in adapting to various shapes and dimensions. Furthermore, the authors introduce a parametric algorithm leveraging Rhinoceros and Grasshopper digital tools, facilitating the manipulation of tessellations' dimensions, quantity, and line thickness. This algorithm generates intricate three-dimensional models amenable to 3D printing technology. The research concludes with an insightful analysis of the potential applications of these technologies, emphasizing their inherent advantages and the challenges they pose for design and innovation across multiple domains of knowledge. By shedding light on the transformative capabilities of parametric design and auxetic structures, this work underscores their significance in fostering innovation and pushing the boundaries of traditional design paradigms.

Nanosized materials with small diameters are known to be excellent for various applications such as catalysis, the sensing of biologically active species, and imaging, or for their anti-oxidant and anti-bacterial activity [1]. Noble metal nanoclusters (NCs) consisting of several atoms have been gaining much attention as novel fluorescent markers owing to their optical properties, which include their size-dependent emission wavelength. In the present study, we use the green synthesis of monometallic and bimetallic nanostructures with bovine serum albumin serving as a template, similarly to one of our previous works [2]. We have investigate the behavior of platinum-containing nanosystems generated by different reducing agents, varying the reactant molar ratios, varying the synthesis approach, and introducing the second metal. Pt NCs show fluorescence emission peak in the range of 450-470nm (370 nm excitation wavelength). Different molar ratios of the reactants have been used to optimize the fluorescent properties of monometallic and bimetallic Pt-containing NCs. The change in the reactants' molar ratios affected the fluorescence intensity and position of the fluorescence emission maximum. Other factors affecting the fluorescent characteristics of these metallic NCs are still under investigation. The as-prepared luminescent NCs can be utilized as contrast agents and/or biomarkers, which is going to be tested in the near future. Moreover, they could play a role in catalytic activity and biosensing, as known from the literature [3].

References

[1] Huang, X., Li, Z., Yu, Z., Deng, X., & Xin, Y. (2019). Recent advances in the synthesis, properties, and biological applications of platinum nanoclusters. Journal of Nanomaterials, 2019.

[2] Ostruszka, R., Půlpánová, D., Pluháček, T., Tomanec, O., Novák, P., Jirák, D., & Šišková, K. (2023). Facile One-Pot Green Synthesis of Magneto-Luminescent Bimetallic Nanocomposites with Potential as Dual Imaging Agent. Nanomaterials, 13(6), 1027.

[3] Xu, N., Li, H. W., Yue, Y., & Wu, Y. (2016). Synthesis of bovine serum albumin-protected high fluorescence Pt16-nanoclusters and their application to detect sulfide ions in solutions. Nanotechnology, 27(42), 425602.

All natural organisms have adapted themselves for survival over millions of years of evolution. For example, snakes have developed nanofeatures on their ventral scales in specific geometry and orientation to ease their locomotion. In addition to that, some snakes have also optimized their scales to control their thermoregulatory and optical properties. Some snakes living in hot and humid equatorial climates have developed reflective white ventral scales to avoid overheating caused by highly radiative soil and rocks. Our analysis shows that nanopores embedded inside these ventral scales scatter light to achieve reflective white surfaces. Interestingly, they are also highly reflective in the near-infrared regime of the electromagnetic spectrum, which might help them to avoid overheating. In comparison with these reflective scales, amorphous structures, rather than nanopores, have been found in transparent/translucent scales. These transparent/translucent scales showed greatly reduced reflective qualities in visible and near-infrared light. Some snakes have developed silvery-white ventral scales. Instead of nanopores, alternating layers of microcavities are found in the scales of these species. Our experimental results suggest that these layers interact with visible light to develop silvery-white surfaces utilizing a “chirped mirror” mechanism. In my presentation, I will discuss several examples of how snakes optimize their optical properties.

The insect cuticle is a multifunctional biological material. One of its striking characteristics is the wide range of its mechanical properties. The elastic modulus of insect cuticle, for example, covers a range of more than eight orders of magnitude [1]. Why do cuticle properties vary so dramatically? To address this question, researchers have used a set of different testing methods to measure the properties of cuticle specimens, which have been selected from various body parts across a variety of insect species and often preserved/prepared in different ways [2,3]. However, almost all these factors can influence the obtained data. Hence, the literature data cannot be simply compared with each other, and no solid conclusion can be drawn regarding the mechanisms that underlie the property variations in the cuticle. To fill this gap in the literature, our studies are focused on two key questions. First, how do the mechanical properties of insect cuticle differ in a single species when all testing conditions are kept constant? Second, what are the mechanisms behind the wide range of cuticle properties? Using a combination of scanning electron microscopy (SEM), micro-computed tomography (micro-CT), confocal laser scanning microscopy (CLSM) and nanoindentation, we performed one of the most comprehensive studies to date, where we simultaneously investigated the microstructure, sclerotization and the elastic modulus of locust cuticle from different body parts. We have shown that, in the desert locust Schistocerca gregaria, the elastic moduli of tibiae, femora and compound eyes range from 0.5 GPa to 8 GPa [4-7]. This property change can be explained almost fully by the differences in the microstructure and sclerotization of the investigated specimens. We expect that our results will help to better understand the complex structure–material–function relationship in insect cuticle. In addition, the detailed data obtained might be potentially interesting for the biomimetic development of strong composite materials for various applications.

Many natural structures, while being lightweight and porous, exhibit respectable levels of stiffness. Natural structural designs are complex and hierarchical, and with the surge in societal demand for lighter weight, durable, yet resilient materials, there is a concurrent research need to consider biomimetic materials as alternatives to traditional materials since these can be manufactured more easily now than ever before, with significant advancements made in the area of digital design and manufacture. Our study considered porous Bouligand structures, which are structures built up of twisting fibrous architecture, but with spaces set between the fibres which induce porosity into the structure. These are more complicated than non-porous Bouligand structures, since the addition of porosity into the material creates a secondary variable besides fibre pitch. As such, there is currently no analytical model available to predict the modulus of such materials.

Our paper explores the correlation between porosity, polymer fibre pitch angle, and flexural modulus in porous-Bouligand-structured polymers. Our structures were digitally manufactured using SLA additive manufacturing methods, after which they were subjected to three-point bending tests. Our aim was to simply and parametrically develop an analytical model that would capture the influences of both porosity and polymer fibre pitch angle on the flexural modulus of the material.

Our model is shown below and we derive this by applying non-linear regression to our experimental data.

This model predicts the flexural modulus, , of porous-Bouligand-structured polymer as a function of both porosity and pitch angle. Here, is a linear reduction of the modulus as a function of increasing porosity and is defined as the solid material modulus, , multiplied by porosity, , while signifies the polymer fiber pitch angle. This relationship is relatively accurate within the range of 10⁰ ≤ ≤ 50⁰ and for porosity values in the range 0.277 ≤ ≤ 0.356, as supported by our evidence to date.

The Bombyx mori silk cocoon serves as a protective covering around the pupa; its mechanical construction should therefore be resistant to predatorial attacks such as punctures, perforations and tears. The B. mori cocoon's resistance to such modes of damage is nevertheless still largely undocumented. The work presented here is part of a broad endeavour to describe the damage tolerance of B. mori silk cocoons. Here, we evaluate two different testing methods using an Instron-3369 testing apparatus to determine its resistance to stabbing by an HOSDB-standard knife. In the first method, the cocoon is stabbed through in its entirety (i.e. through an uncut and unimpaired structure), while in the second approach, the cocoon is cut open to form a rectangular quasi-flat sheet of cocoon wall which is tightly clamped prior to being punctured by the knife stab. The stabbing force was measured in both techniques. While the stabbing forces needed to puncture and perforate full cocoons and rectangular walls were approximately the same, there were noticeable differences in the force vs. extension curves in each stabbing method. The analysed results imply that it is preferable to directly test full cocoon walls rather than to artificially pre-prepare the cocoon wall into quasi-flat sheets and to then forcibly constrain them at specific edge locations of the quasi-flat sheet. This is because the artificial pre-preparation of cocoon walls forces them to adopt an unnatural geometrical form (quasi-flat) and, as a consequence, the wall deforms in an unnatural manner during the penetration stage of stabbing. This is an important finding since the vast majority of the mechanical testing research published utilises cut and quasi-flattened cocoon walls. There is currently no standardised test method for the puncture and perforation of material from B. mori cocoons. In conclusion, our research provides new insights into their preparation and testing.

While commercially available lightweight "stab-proof" apparel exists, these offer little resistance to true stabbing as they are primarily designed to withstand slash attacks. Yet, crimes involving the use of a knife or sharp instrument have consistently been rising in the UK over the course of several decades. For the most part, the various proposed solutions to stab-proofing are based on speciality textiles, and while these have shown success in slash-proofing, their utility for stab-proofing is still somewhat unknown. Nature showcases a plethora of puncture-resisting materials and structures. At the macroscale, these include carapaces, egg cases, toughened skin, and more. One of the most effective protective mechanisms known comes through surface scaling, present on animals such as reptiles and fish. Scaled protective armours present in extant fish species include overlapping elasmoid scales, interlocking ganoid scales, placoid scales, tessellating carapace scutes, and interlocking plates. Here, we research overlapping and interlocking scaled structures to ascertain the stab penetration resistance of biomimetic scaled structures against continuum material. We use additive manufacturing methods to manufacture biomimetic armour made of nylon, a common protective artificial material used in slash-proofing textiles. Stab-testing the HOSBD body armour standard 2017, we find that biomimetic scales made of nylon offer greater protection against direct stabbing, than continuum nylon material sheets do. This can be attributed to (a) heightened flexibility in an interlocked fish scale structure that does not exist in a continuum sheet of the same material and (b) the effect of the fish scales overlapping, resulting in a greater penetration depth requirement before the structure undergoes perforation.

In line with Sustainable Development Goal 9 (sustainable industrialisation and innovation), environmentally responsible engineering designs in modern robotics should consider factors such as renewability, sustainability, and biodegradability. The robotics sector is growing at an exponential rate, and as a consequence, its contribution to e-waste is a growing concern. Our work contributes to the technology development of caninoid necro-robots, robots that are built from the skeletons of deceased dogs. The already formed skeletal structures of deceased dogs (and other animals) are ideal natural material replacements for synthetic robotic architectures such as plastics, metals, and composites. Since dog skeletons are disarticulated, simple but effective methods need to be developed to rearticulate their bodies. The canine skull is essentially a large end effector, but its mandible is held together by a fibrocartilaginous joint (symphysis) that degrades at a higher rate than the bone itself. The degradation of the symphysis would ordinarily negate the utility of a canine skull as a necro-robotic end effector; however, in this research, we consider simple methods of mandible reinforcement to circumvent this problem. Our research uses 3D scans of a real canine skull, which is modelled using the finite element method to ascertain optimal geometrical reinforcements for the mandible. The full skull structures and their reinforcements are printed and adhesively connected to determine the most effective reinforcing strategy for the mandible. Here, we elucidate geometrically selected reinforcement designs that are evidenced through mechanical testing, to successfully increase the stiffness of a disarticulated mandible.