Design of kinematic connectors for microstructured materials produced by additive manufacturing

The main characteristic of materials with a functional gradient is the progressive composition or the structure variation across its geometry. This results in the properties variation in one or more specific directions, according to the functional application requirements. Cellular structure flexibility in tailoring properties is employed frequently to design functionally-graded materials. Topology optimisation methods are powerful tools to functionally graded materials design with cellular structure geometry, although continuity between adjacent unit-cells in gradient directions remains a restriction. It is mandatory to attain a manufacturable part to guarantee the connectedness between adjoining microstructures, namely by ensuring that the solid regions on the microstructure’s borders i.e., kinematic connectors) match the neighboring cells that share the same boundary. This study assesses the kinematic connectors generated by imposing local density restrictions in the initial design domain (i.e., nucleation) between topologically optimised representative unit-cells. Several kinematic connector examples are presented for two representatives unit-cells topology optimised for maximum bulk and shear moduli with different volume fractions restrictions and graduated Young’s modulus. Experimental mechanical tests (compression) were performed, and comparison studies were carried out between experimental and numerical Young’s modulus. The results for the single maximum bulk for the mean values for experimental compressive Young’s modulus (Ex¯) with 60%Vf show a deviation of 9.15%. The single maximum shear for the experimental compressive Young’s modulus mean values (Ex¯) with 60%Vf, exhibit a deviation of 11.73%. For graded structures, the experimental mean values of compressive Young’s moduli (Ex¯), compared with predicted total Young’s moduli (ESe), show a deviation of 6.96 for the bulk graded structure. The main results show that the single type representative unit-cell experimental Young’s modulus with higher volume fraction presents a minor deviation compared with homogenized data. Both (i.e., bulk and shear moduli) graded microstructures show continuity between adjacent cells. The proposed method proved to be suitable for generating kinematic connections for the design of shear and bulk graduated microstructured materials.This research was funded by the Portuguese Science Funding Foundation FCT—Fundação para a Ciência e a Tecnologia (Grant No. SFRH/BD/130908/2017); PAMI—Portuguese Additive Manufacturing Initiative (Project nº22158—SAICT—AAC—01/SAICT/2016), CDRSP (UIDB/04044/2020), (UIDP/04044/2020); Add.Additive—add additive manufacturing to Portuguese industry (POCI-01- 0247-FEDER-024533)

Geologia Sul Portuguesa, com ênfase na estratigrafia, vulcanologia física, geoquímica e mineralizações da faixa piritosa

O presente trabalho resulta da adaptação e actualização do artigo «O Complexo Vulcano--Sedimentar da Faixa Piritosa: Estratigrafia, Vulcanismo e Mineralizações Associadas no Contexto da Zona Sul Portuguesa» de autoria de Oliveira et al., inserido no Livro Geologia de Portugal no Contexto da Ibéria, editado por Rui Dias, Alexandre Araújo, Pedro Terrinha e Carlos Kulberg e publicado pela Universidade de Évora, em 2006, durante o VII Congresso Nacional de Geologia

Mechanical properties of Graphene Nanoribbons

Herein, we investigate the structural, electronic and mechanical properties of zigzag graphene nanoribbons upon the presence of stress applying Density Functional Theory within the GGA-PBE approximation. The uniaxial stress is applied along the periodic direction, allowing a unitary deformation in the range of +/- 0.02%. The mechanical properties show a linear-response within that range while the non-linear dependence is found for higher strain. The most relevant results indicate that Young's modulus is considerable higher than those determined for graphene and carbon nanotubes. The geometrical reconstruction of the C-C bonds at the edges hardness the nanostructure. Electronic structure features are not sensitive to strain in this linear elastic regime, being an additional promise for the using of carbon nanostructures in nano-electronic devices in the near future.Comment: 30 pages. J. Phys.: Condens. Matter (accepted

Nanoencapsulation of quercetin into bio-based nanostructures obtained from assembling of α-lactalbumin and lysozyme

Nanotechnology possesses an intrinsic potential to produce new food ingredients and innovative products, with considerable benefits to human health. This can be attained via development of innovative structures for application in functional foods. In recent years, consumption of foods providing health benefits has risen chiefly as a result of significant investments from the food industry and widening consumer awareness in this field. Polyphenols constitute one such functional ingredient: it entails a large group of plant metabolites with a large spectrum of recognized biological activities in humans. Quercetin is, in particular, one of the most representative compounds of the flavonoid family; it has been assigned a wide range of health benefits, including anti-inflammatory agent, cancer prevention, DNA protection agent, antioxidant and cardio-protective agent. However, its bioavailability is low, so limited biological effects may be noticed arising from its poor solubility, gastrointestinal instability and low uptake rate through the gastrointestinal tract. A possible solution to overcome such limitations is nanoencapsulation of quercetin. Therefore, our study was aimed at encapsulating quercetin into bio-based nanostructures obtained from assembling of α-lactalbumin (α-La) and lysozyme (Lys), as promoted by heating at 75 oC for 15 min, at pH 11; evaluation of their association efficiency was performed. Such nanostructures were prepared via solubilization of 2 mg mL-1 of Lys and α-La powders in water, at a molar ratio of 1:0.54, and were extensively characterized by dynamic light scattering (for particle size, polydispersity and zeta potential) and transmission electron microscopy (for microstructure and morphology). Quercetin has been successfully encapsulated into protein nanostructures above 50% efficiency. These nanostructures exhibited spherical morphology, with average size below 100 nm and zeta potential around -35 mV. Our results suggest that quercetin encapsulated in such proteinaceous nanostructures may be used for manufacture of functional foods

Design of bio-based supramolecular structures through self-assembly of α-lactalbumin and lysozyme

Bovine α-lactalbumin (α-La) and lysozyme (Lys), two globular proteins with highly homologous tertiary structures and opposite isoelectric points, were used to produce bio-based supramolecular structures under various pH values (3, 7 and 11), temperatures (25, 50 and 75 °C) and times (15, 25 and 35 min) of heating. Isothermal titration calorimetry experiments showed protein interactions and demonstrated that structures were obtained from the mixture of α-La/Lys in molar ratio of 0.546. Structures were characterized in terms of morphology by transmission electron microscopy (TEM) and dynamic light scattering (DLS), conformational structure by circular dichroism and intrinsic fluorescence spectroscopy and stability by DLS. Results have shown that protein conformational structure and intermolecular interactions are controlled by the physicochemical conditions applied. The increase of heating temperature led to a significant decrease in size and polydispersity (PDI) of α-La–Lys supramolecular structures, while the increase of heating time, particularly at temperatures above 50 °C, promoted a significant increase in size and PDI. At pH 7 supramolecular structures were obtained at microscale – confirmed by optical microscopy – displaying also a high PDI (i.e. > 0.4). The minimum size and PDI (61 ± 2.3 nm and 0.14 ± 0.03, respectively) were produced at pH 11 for a heating treatment of 75 °C for 15 min, thus suggesting that these conditions could be considered as critical for supramolecular structure formation. Its size and morphology were confirmed by TEM showing a well-defined spherical form. Structures at these conditions showed to be stable at least for 30 or 90 days, when stored at 25 or 4 °C, respectively. Hence, α-La–Lys supramolecular structures showed properties that indicate that they are a promising delivery system for food and pharmaceutical applications.CNPq and CAPES, and their support to FAPEMIG and CNPEM-LNBio (Centro Nacional de Pesquisa em Energia e Materiais-Laboratório Nacional de Biociências) both from Brazil. Fundação para a Ciência e a Tecnologia. The authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, COMPETE 2020 (POCI-01-0145-FEDER-006684), the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), and the project “BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes”, REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER

Multidisciplinary and multi sector lighthouses | case studies | Deliverable D2.2

RES4CITY is a 36-month project funded by the European Commission, initiated in October 2022. Its primary objective is to advance the development of sustainable renewables and fuel technologies within cities. This is achieved by collaborative efforts in designing innovative educational micro-programmes involving various stakeholders. The project also emphasizes the promotion of sustainability and circularity, bridging the knowledge and skills gaps essential for a successful energy transition. This deliverable, designated as D.2.2 RES4CITY multidisciplinary and multi sector lighthouses, is developed under task T2.2 Lighthouse case studies development of the RES4CITY project during M12 (September 2023). Task T2.2 builds upon the energy-related urban challenges identified in T2.1 Innovative sustainable strategies for carbon neutral smart cities. In essence, task T2.2 focuses on creating lighthouse case studies that address these identified challenges. To ensure a comprehensive and effective approach, task T2.2 collaborates closely with task T3.2, actively engaging the community of stakeholders. The culmination of these collaborative efforts results in the production of pre-feasibility analyses tailored to the specific urban context under consideration. The document comprises three chapters. The first chapter introduces task T2.2, which involved the development of ten lighthouse case studies by project partners, along with their corresponding HUBs. This chapter describes the approach to ensuring clarity and enhancing reader comprehension, thereby amplifying the impact and dissemination of these case studies. To achieve this, the case studies followed a predefined template designed with a structure like that of a scientific article. This structure encompasses not only an introductory section addressing the challenge under scrutiny and introducing the case study but also includes sections dedicated to presenting results, recommendations, and conclusions. In the second chapter, the ten lighthouse case studies are compiled and presented individually. This set of lighthouse case studies contributes to fulfilling the RES4CITY’s Milestone 11 Lighthouse available for case study education. Each case study is accompanied by an executive summary, which complements the existing Abstract and Graphical Abstract elements that are part of the case study structure. The objective of creating this executive summary is to provide an additional resource that can be examined independently of the complete case study. Its purpose is to facilitate an understanding of the subject matter and the case study itself while highlighting key results and conclusions. This approach enables the case studies to be used independently. Within the framework of this Deliverable, the executive summary serves as tool for readers to grasp the key points of each case study swiftly and concisely. This empowers readers to determine, based on their interests and requirements, whether they want to delve deeper into the individual case studies for more detailed analysis. In the third and concluding chapter, each lighthouse case study developed by the project partners is presented in a straightforward and concise manner. Furthermore, this chapter highlights key concluding remarques derived from each of the case studies. Lastly, it emphasizes the dual purposes for which these case studies were developed: as learning tools in the RES4CITY learning and upskilling programs and as multipliers for replication in other contexts. The Deliverable 2.2 was concluded and submitted in September 2023 by (UCOI) with the support of the partners listed in Table 1

La carta de Jerusalén: un nuevo paradigma en el cuidado de los niños y adolescentes alérgicos en las escuelas de Latinoamérica

De acuerdo con la Organización Mundial de la Salud, las enfermedades alérgicas ocupan el sexto lugar entre las enfermedades infantiles y representan un tercio de las enfermedades crónicas en los niños. En 1 de cada 5 niños, la enfermedad alérgica se manifiesta en la edad escolar

Design of nanostructures, obtained from assembling of α-lactalbumin and lysozyme upon heat treatment and selective environmental conditions

Protein assembly into supramolecular structures (e.g. aggregates, fibrils and nanotubes) is a widespread phenomenon in biological sciences. Nowadays, it is well documented that the amphiphilic properties of proteins is a driving force to their self-assembling into innovative micro- and nanostructures of high interest in the food and pharmaceutical fields. Formation of such structures is strongly dependent on physicochemical conditions and protein conformation. In this study, bio-based nanostructures were produced from assembly of hen egg white lysozyme (Lys) and bovine α-lactalbumin (α-La) – i.e. two homologous globular proteins with opposite charge), under various processing conditions: heating treatment (55 °C and 75 °C), holding time (25 and 35 min) and pH (3 and 11). The nano-scale structures prepared by solubilization of 2 mg mL-1 of Lys and α-La powders in water, at a molar ratio of 1:0.54, were characterized via dynamic light scattering (in terms of particle size, polydispersity and zeta potential), and further analyzed by transmission electron microscopy (TEM). Smaller sized particles (75 nm) and low podydispersity values (0.24) were produced at pH 11 after heating at 75 °C for 25 min, whereas at pH 3 (and similar conditions) the average mean particle size was ca. 402 nm with polydispersity of 0.45. The nanostructure stability was also assessed; higher stability was obtained at pH 11 than 3, with zeta potentials of -35 and +27 mV, respectively, by 60 d. The nanostructure entities prepared at pH 11 were shown by TEM to possess a well defined spherical shape. Protein assembly mechanisms and intermolecular interactions involved appear to be controlled by the environmental conditions applied; therefore, an understanding of the quantitative effects of these conditions are crucial for rational design of new protein assemblies with tailor-made functionalities