A road map to find in 3D printing a new design plasticity for construction- The state of art

Recent years are showing a rapid adoption of digital manufacturing techniques to the construction industry, with a focus on additive manufacturing. Although 3D printing for construction (3DPC) has notably advanced in recent years, publications on the subject are recent and date a growth in 2019, indicating that it is a promising technology as it enables greater efficiency with fair consumption of material, minimization of waste generation, encouraging the construction industrialization and enhancing and accelerating the construc-tive process. This new building system not only gives an optimization of the building process but provides a new approach to the building design materiality. The direct connection between design and manufacturing allows the reduction in the number of the various construction phases needed. It is opening a new and wide range of options both formal and chromatic in customization, avoiding complex formworks, reducing costs and manufacturing time. The cre-ative process has a strict and direct link with the constructive process, straightening design with its materiality. Cement-based materials lead the way, but new alternatives are being explored to further reduce its carbon footprint. In order to leverage its sustainability and enhance the system capacity, initiatives are being pursued to allow the reduction of the use of PC. Geopolimers are taking the first steps in 3DPC. Construction and Demolition Waste (CDW) materials are used to substitute natural aggregates. Even soil is being explored has a structural and aesthetic material. These research trends are opening a wider range of possibil-ities for architecture and design, broadening the spectrum of color, texture, and formal variations. The concern about textures and colours is not yet evident in many the structures already printed, opening the opportunity for future research. More can be done in the mixture and formal design of this building system, discovering other raw materials in others waste. This article aims to make a critical review of technologies, materials and methodologies to sup-port the development of new sustainable materials to be used as a plastic element in the printed structure. A roadmap of 3D printing for construction is presented, and an approach on mix design, properties in the fresh and hardened state, highlighting the possibilities for ob-taining alternative materials are pointed. With this review possible directions are presented to find solutions to enhance the sustainability of this system discovering new materiality for ar-chitecture and design.(c) 2022 Higher Education Press Limited Company. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/)

Influence of Supplementary Cementitious Materials on Fresh Properties of 3D Printable Materials

The development of printers and materials for 3D Printing Construction during the last two decades has allowed the construction of increasingly complex projects. Some of them have broken construction speed records due to the simplification of the construction process, particularly in non-standard geometries. However, for performance and security reasons the materials used had considerable amounts of Portland cement (PC), a constituent that increases the cost and environmental impact of 3D Printable Materials (3DPM). Supplementary Cement Materials (SCM), such as fly ash, silica fume and metakaolin, have been considered a good solution to partially replace PC. This work aims to study the inclusion of limestone filler, fly ash and metakaolin as SCM in 3DPM. Firstly, a brief literature review was made to understand how these SCM can improve the materials' 3DP capacity, and which methods are used to evaluate them. Based on the literature review, a laboratory methodology is proposed to assess 3DP properties, where tests such as slump and flow table are suggested. The influence of each SCM is evaluated by performing all tests on mortars with different dosages of each SCM. Finally, a mechanical extruder is used to extrude the developed mortars, which allowed us to compare the results of slump and flow table tests with the quality of extruded samples. (c) 2022 by the authors. Licensee MDPI, Basel, Switzerland

Industrial and natural waste transformed into raw material

Currently, we live in a world where the materials are the protagonists. Raw materials are fundamental to make industrial products; however, the increasing demand for these finite natural resources put the more industrialized countries under pressure to find ways to recycle and reuse the products at the end of their lives. Every year, tons of industrial and natural waste are accumulated and destroyed without a new use for them. Today, the energy consumption at the world level to extract raw materials contributes significantly to pollution and environmental degradation. In the European Union, the construction sector is responsible for 40% of global energy consumption, contributing considerably to CO2 emissions. The planet's future is compromised, unless the human beings learn how to preserve and conserve resources that Earth offers, changing the basic patterns of consumption, manufacturing and recycling. Sofa industries and wood industries generate significant amounts of waste that undergo a thoughtless destruction or recycling with a final order to reuse. This paper presents the research work that has been conducted in the scope of the Master Program in Product and Industrial Design of Faculty of Engineering, Faculty of Fine Arts and Design Studio FEUP, seeking the reuse of leftovers (textile and wood powder), to create innovative products. The main objective is to prepare the waste that is mixed with different amounts and types of binders, and cast in molds. In some cases, the introduction of a shape memory alloy can promote an extra value and functionality to the designed products. This way the aim is to sensitize the community to the possibility of introducing new products in the market addressing concepts such as green design, sustainability and innovation

Enzymatic Synthesis of Inulin-Containing Hydrogels

The Bacillus subtilis protease Proleather FG-F catalyzed the transesterification of inulin with vinyl acrylate (VA) in dimethylformamide (DMF). The reaction conversion for different VA concentrations was greater than 57% after 96 h at 50 °C. The degree of substitution (DS, defined as the amount of acrylate groups per 100 inulin fructofuranoside residues) with acrylate moieties can be controlled by varying the molar ratio of VA to inulin. Reasonable yields were obtained (44−51%, 2 days) using a two-step purification methodology. Inulin derivatized with VA (Inul-VA) was characterized by gel permeation chromatography, and its structure was established by 1H, 13C, and 1H−1H correlation spectroscopy and 1H−13C heteronuclear multiple quantum coherence NMR. The main positional isomer was at the 6 position of the fructofuranoside residue and two other minor isomers were observed at the 3 and 4 positions. Thus, the enzymatic reaction was largely regioselective. Furthermore, the inulin fructose residues were monosubstituted. Gels with swelling ratios at equilibrium of up to ca. 20 were prepared by free radical polymerization of aqueous solutions of Inul-VA with different DS and monomer concentrations. Gel pore sizes were calculated from swelling experiments and range from 19 to 57 Å. To our knowledge, this work reports the first successful enzymatic modification of a polysaccharide solubilized in 100% DMF solution

Pulsatile tinnitus - Case report of duralarteriovenous fistula and review of the literature

O acufeno é definido como uma percepção consciente de um som na ausência de fonte externa. Embora não seja considerado uma doença, muitos doentes sofrem deste sintoma. Tem múltiplas etiologias sendo que, apenas algumas são conhecidas. As malformações vasculares constituem a principal causa de acufenos pulsáteis. Descrevem-se dois casos clínicos de doentes com acufeno pulsátil. Ambos realizaram angio-ressonância que evidenciou fístula arteriovenosa dural (DAVF) do seio lateral direito, uma do tipo I e outra do tipo IIa de Cognard. Foram submetidas a angiografia crânioencefálica com embolização, recorrendo a partículas de polivinil álcool (PVA) e a Onyx®, com encerramento da fístula e resolução das queixas. O tratamento das fístulas arteriovenosas durais deve ser ponderado de acordo como tipo de fístula, segundo as escalas de Cognard ou de Borden e, com a existência ou não de sintomatologia.info:eu-repo/semantics/publishedVersio

CONSIDERAÇÕES KANTIANAS SOBRE OS GÊNEROS

O texto proposto apresenta a descrição kantiana dos gêneros e as relações entre estes através das obras: Observações sobre o sentimento do belo e do sublime (1764) e Antropologia de um ponto de vista Pragmático (1798). Na primeira, os gêneros são determinados através das categorias estéticas do belo e sublime. A partir da distinção estabelecida entre os sentimentos de prazer, as virtudes morais e os caracteres psicológicos ocupam um lugar determinado e assim se elabora o conceito da diferença entre os sexos. Já na Antropologia, o homem é tratado como cidadão do mundo. Trata-se do sujeito que é atingido por regras jurídicas precisas e ainda assim age livremente

An overview of the hooking mortality of elasmobranchs caught in a swordfish pelagic longline fishery in the Atlantic Ocean

Hooking (or “at-haulback”) fishing mortality was analysed in elasmobranchs captured by Portuguese longliners targeting swordfish in the Atlantic Ocean. Information was collected by on-board fishery observers who monitored 834 longline fishing sets between August 2008 and December 2011, and recorded information on 36,067 elasmobranch specimens from 21 different taxa. The hooking mortality proportions were species-specific, with some species having relatively high percentages of live specimens at time of haulback (e.g., blue shark, crocodile shark, pelagic stingray, manta, devil and eagle rays), while others had higher percentages of dead specimens (e.g., smooth hammerhead, silky shark, bigeye thresher). For the most captured species, logistic GLMs were carried out to compare the mortality rates between sexes, specimen sizes and the regions of operation of the fleet. The sex-specific proportions of hooking mortality were significantly different for blue and crocodile sharks, with the males of both species having higher proportions of hooking mortality than the females. Specimen size was significant for predicting the hooking mortality for blue and shortfin mako sharks: in both cases, the larger specimens had lower odds of dying due to the fishing process. There were differences in the hooking mortality depending on the region of operation of the fleet, but those differences were also species-specific. For blue and crocodile sharks, the hooking mortality was higher in the Equatorial and southern Atlantic areas (when compared to the NE Atlantic region), while the opposite was observed for the shortfin mako, with lower mortality rates in the NE tropical area compared with the other regions. The results presented in this paper can be integrated into future ecological risk assessment analysis for pelagic elasmobranchs. Furthermore, the new information can be used to evaluate the impact of recent recommendations prohibiting the retention of some vulnerable elasmobranch species

Formas de resolución de laberintos por alumnos de escuelas primarias

Saber planejar expressa uma forma de antecipação com pré-correção de erros e uso de inferências. Esta questão foi aqui analisada em 60 matrizes de labirintos (20 A, 20 B e 20 C), resolvidas por 20 alunos da Escola Fundamental, entre 7 e 11 anos. Deste total, 31 matrizes foram resolvidas com um único traçado. As 29 restantes foram analisadas, considerando-se, dentre outros, procedimentos indicadores de planejamento: (1) começar do final, (2) aproveitar o traçado anterior e (3) interromper o traçado. O procedimento (1) foi utilizado pelos sujeitos em 7 matrizes; o procedimento (2) em 9; e o procedimento (3) em 5. Na discussão, apoiada em estudos comparáveis realizados por Piaget, destacaram-se três níveis de resolução das matrizes utilizadas. E, nas considerações finais, foram descritas algumas formas de intervenção, visando favorecer, em um contexto educacional, o desenvolvimento da habilidade de antecipação em crianças.Planning means to anticipate by pre-correcting mistakes and making use of inferences. This statement was analyzed in this study in which 60 labyrinths (20A, 20B and 20C) were solved by 20 elementary school students aged between 7 and 11 years old. From the total amount, 31 were solved with one single line. The remaining ones were closer studied and it was possible to identify three indicators of planning procedures: procedure (1) beginning from the end; procedure (2) use part of the former line; (3) stopping a wrong line before the end. Procedure (1) appeared on 7 labyrinths, (2) on 9 and (3) on 5 of them. The discussion, based on studies held by Piaget, brings up the possibility to underline three different levels of resolution. In the conclusion, possible forms of intervention are presented, aiming to suggest that, in educational contexts, labyrinths may be used to develop the anticipation skill on children who play.El saber planificar expresa una forma de anticipación con pre-corrección de errores y uso de deducciones. Esta cuestión fue analizada aquí en 60 matrices de laberintos (20 A, 20 B y 20 C) resueltas por alumnos de escuelas primarias, entre 7 y 11 años. Del total, 31 matrices fueron resueltas con un único trazo. Las 29 restantes fueron analizadas, considerándose, entre otros, procedimientos indicadores de planificación: (1) comenzar del final, (2) aprovechar el trazo anterior y (3) interrumpir el trazo. Los sujetos utilizaron el procedimiento (1) en 7 matrices; el procedimiento (2) en 9; y el procedimiento (3) en 5. En la discusión, con base en estudios comparables efectuados por Piaget, se destacaron tres niveles de resolución de las matrices usadas. Y en las consideraciones finales fueron descritas algunas formas de intervención, con la finalidad de favorecer, en un contexto educacional, el desarrollo de la habilidad de anticipación en los niños

Science-based solutions to foster connectivity of wolf populations are limited by available data

European wolf populations are currently exposed to distinct sources of anthropogenic disturbance and mortality that can cause dispersal limitations and lead to isolation. The identification of factors that act as complete or partial barriers to movement, dispersal, or gene flow contribute to foster connectivity between populations. We reviewed the existing literature (N=32) on wolf population barriers to 1) identify main barriers to connectivity; 2) outline different methodologies; and 3) highlight knowledge gaps. Based on the reviewed studies that empirically tested barrier occurrence (N=14), we compiled data on wolf population structure, anthropogenic disturbance, land cover, ecological factors, geographical features, and prey availability, and tested them as predictors to explain barrier occurrence at continental scale. We report few studies directly addressing this subject for one of the most emblematic and thoroughly studied species, inhabiting one of the most modified landscapes in the world. Albeit our analysis suggested that anthropogenic features are the main drivers of barrier occurrence, we highlight that the absence of standardised data limits our understanding of this subject. Long-term, intensive monitoring programs, explicit hypothesis-driven research using empirical methodologies, and the integration of information on databases for collaborative science are needed to increase the conservation and management relevance of future scientific outcomes on this topic.info:eu-repo/semantics/publishedVersio