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The surge in global population growth and the escalating demand for social and economic prosperity present formidable challenges in the 21st century. However, asserting the sustainability of some ecological impact reduction initiatives, such as recycling, requires a comprehensive evaluation within various domains, including performance, ecology, and economics, and contemporary advancements in integrating quantitative assessments of material and manufacturing properties, coupled with mathematical decision-making approaches, contribute to mitigating subjectivity in determining the efficiency of recycling. This paper implements a robust multi-criteria decision-making (MCDM) approach to address the complexities of recycling, validating its implementation and effectiveness through a case study. The focus is set on the application of bio-based polylactic acid (PLA) and petroleum-based polypropylene (PP) additively manufactured (AM) parts produced through Fused Filament Fabrication (an approach to ecology/performance domains). The work introduces a cost analysis focusing on calculating thermomechanical recycling within the economic domain. The well-known Analytical Hierarchical Process (AHP) provides a structured framework for decision-making (the ecological impact domain) with the focus being on application. The assessment or recycling viability, encompassing AHP calculations, preprocessing, and supplementary tools, is provided by developing an open-source software tool for practitioners in the field of material science and manufacturing. The results indicate a preference for industrial-scaled recycling over virgin or lab-recycled manufacturing, particularly for petroleum-based polypropylene. The versatility and simple utilization of the software tool allow seamless integration for diverse use cases involving different materials and processes.

Arctic plant communities are altered by climate changes. The magnitude of these alterations depends on whether species distributions are determined by macroclimatic conditions, by factors related to local topography, or by biotic interactions. Our current understanding of the relative importance of these conditions is limited due to the scarcity of studies, especially in the High Arctic. We investigated variations in vascular plant community composition and species richness based on 288 plots distributed on three sites along a coast‐inland gradient in Northeast Greenland using a stratified random design. We used an information theoretic approach to determine whether variations in species richness were best explained by macroclimate, by factors related to local topography (including soil water) or by plant‐plant interactions. Latent variable models were used to explain patterns in plant community composition. Species richness was mainly determined by variations in soil water content, which explained 35% of the variation, and to a minor degree by other variables related to topography. Species richness was not directly related to macroclimate. Latent variable models showed that 23.0% of the variation in community composition was explained by variables related to topography, while distance to the inland ice explained an additional 6.4 %. This indicates that some species are associated with environmental conditions found in only some parts of the coast–inland gradient. Inclusion of macroclimatic variation increased the model's explanatory power by 4.2%. Our results suggest that the main impact of climate changes in the High Arctic will be mediated by their influence on local soil water conditions. Increasing temperatures are likely to cause higher evaporation rates and alter the distribution of late‐melting snow patches. This will have little impact on landscape‐scale diversity if plants are able to redistribute locally to remain in areas with sufficient soil water. Arctic plant communities are altered by climate changes. Our results strongly suggest that the main impact of climate changes in the High Arctic will be mediated by their influence on local soil water availability.

Arthropods form a major part of the terrestrial species diversity in the Arctic, and are particularly sensitive to temporal changes in the abiotic environment. It is assumed that most Arctic arthropods are habitat generalists and that their diversity patterns exhibit low spatial variation. The empirical basis for this assumption, however, is weak. We examine the degree of spatial variation in species diversity and assemblage structure among five habitat types at two sites of similar abiotic conditions and plant species composition in southwest Greenland, using standardized field collection methods for spiders, beetles and butterflies. We employed non-metric multidimensional scaling, species richness estimation, community dissimilarity and indicator species analysis to test for local (within site)- and regional (between site)-scale differences in arthropod communities. To identify specific drivers of local arthropod assemblages, we used a combination of ordination techniques and linear regression. Species richness and the species pool differed between sites, with the latter indicating high species turnover. Local-scale assemblage patterns were related to soil moisture and temperature. We conclude that Arctic arthropod species assemblages vary substantially over short distances due to local soil characteristics, while regional variation in the species pool is likely influenced by geographic barriers, i.e., inland ice sheet, glaciers, mountains and large water bodies. In order to predict future changes to Arctic arthropod diversity, further efforts are needed to disentangle contemporary drivers of diversity at multiple spatial scales.

By the establishment of the Greenland Botanical Survey in 1962 at the Botanical Museum, University of Copenhagen, an era of regular and systematic exploration of the vascular plant flora of Greenland was initiated and it ended in 1996, when funding ended. Preceding this period, the vascular plant flora was mainly known from the results of more sporadic botanical investigations mostly in low arctic West and East Greenland, but after the 1980s, investigations expanded to include the more inaccessible high arctic Northeast and North Greenland. Nowadays, vascular plant species have been collected from most regions of Greenland. So far, three regional phytogeographical studies of South, North, and West Greenland have been published, and at present, two papers dealing with the vascular plant flora of East Greenland are ready for publication. These studies will be the basis for a synopsis of the phytogeography of Greenland and a new edition of the Flora of Greenland. The published distribution maps from South, West, and North Greenland based on these collections have been digitized and used for modelling the regional vegetation and flora and its relation to past glaciations and current climate. The specimens from East Greenland have been entered into a database and will be available for future modelling projects.

Polymers have a reputation for several advantageous characteristics like chemical resistance, weight reduction, and simple form-giving processes. The rise of additive manufacturing technologies such as Fused Filament Fabrication (FFF) has introduced an even more versatile production process that supported new product design and material concepts. This led to new investigations and innovations driven by the individualization of customized products. The other side of the coin contains an increasing resource and energy consumption satisfying the growing demand for polymer products. This turns into a magnitude of waste accumulation and increased resource consumption. Therefore, appropriate product and material design, taking into account end-of-life scenarios, is essential to limit or even close the loop of economically driven product systems. In this paper, a comparison of virgin and recycled biodegradable (polylactic acid (PLA)) and petroleum-based (polypropylene (PP) & support) filaments for extrusion-based Additive Manufacturing is presented. For the first time, the thermo-mechanical recycling setup contained a service-life simulation, shredding, and extrusion. Specimens and complex geometries with support materials were manufactured with both, virgin and recycled materials. An empirical assessment was executed through mechanical (ISO 527), rheological (ISO 1133), morphological, and dimensional testing. Furthermore, the surface properties of the PLA and PP printed parts were analyzed. In summary, PP parts and parts from its support structure showed, in consideration of all parameters, suitable recyclability with a marginal parameter variance in comparison to the virgin material. The PLA components showed an acceptable decline in the mechanical values but through thermo-mechanical degradation processes, rheological and dimensional properties of the filament dropped decently. This results in significantly identifiable artifacts of the product optics, based on an increase in surface roughness.

En 1850 Thomas Carlyle definió a los economistas aca­démicos como los “respetables profesores de la ciencia oscura”, y desde entonces “la economía todavía no ha podido quitarse tal calificativo”, nos dice John Ken­neth Galbraith. En la opinión de Carlyle, los econo­mistas eran hombres de ciencia que consideraban que las desigualdades económicas jamás desaparecerían y que siempre habría clases privilegiadas, opinión que parece ser compartida por algunos otros estudiosos de las ciencias sociales, a quienes tal vez les parezca que la imagen que ofrecen el sufrimiento y la miseria, consti­tuye el mejor de los mundos posibles.

We present a comprehensive list of non-native vascular plants known from the Arctic, explore their geographic distribution, analyze the extent of naturalization and invasion among 23 subregions of the Arctic, and examine pathways of introductions. The presence of 341 non-native taxa in the Arctic was confirmed, of which 188 are naturalized in at least one of the 23 regions. A small number of taxa (11) are considered invasive; these plants are known from just three regions. In several Arctic regions there are no naturalized non-native taxa recorded and the majority of Arctic regions have a low number of naturalized taxa. Analyses of the non-native vascular plant flora identified two main biogeographic clusters within the Arctic: American and Asiatic. Among all pathways, seed contamination and transport by vehicles have contributed the most to non-native plant introduction in the Arctic.

Warming-induced expansion of trees and shrubs into tundra vegetation will strongly impact Arctic ecosystems. Today, a small subset of the boreal woody flora found during certain Plio-Pleistocene warm periods inhabits Greenland. Whether the twenty-first century warming will induce a re-colonization of a rich woody flora depends on the roles of climate and migration limitations in shaping species ranges. Using potential treeline and climatic niche modelling, we project shifts in areas climatically suitable for tree growth and 56 Greenlandic, North American and European tree and shrub species from the Last Glacial Maximum through the present and into the future. In combination with observed tree plantings, our modelling highlights that a majority of the non-native species find climatically suitable conditions in certain parts of Greenland today, even in areas harbouring no native trees. Analyses of analogous climates indicate that these conditions are widespread outside Greenland, thus increasing the likelihood of woody invasions. Nonetheless, we find a substantial migration lag for Greenland's current and future woody flora. In conclusion, the projected climatic scope for future expansions is strongly limited by dispersal, soil development and other disequilibrium dynamics, with plantings and unintentional seed dispersal by humans having potentially large impacts on spread rates.

AIM: The Arctic has experienced marked climatic differences between glacial and interglacial periods and is now subject to a rapidly warming climate. Knowledge of the effects of historical processes on current patterns of diversity may aid predictions of the responses of vegetation to future climate change. We aim to test whether plant species and genetic diversity patterns are correlated with time since deglaciation at regional and local scales. We also investigate whether species richness is correlated with genetic diversity in vascular plants. LOCATION: Circumarctic. METHODS: We investigated species richness of the vascular plant flora of 21 floristic provinces and examined local species richness in 6215 vegetation plots distributed across the Arctic. We assessed levels of genetic diversity inferred from amplified fragment length polymorphism variation across populations of 23 common Arctic species. Correlations between diversity measures and landscape age (time since deglaciation) as well as variables characterizing current climate were analysed using spatially explicit simultaneous autoregressive models. RESULTS: Regional species richness of vascular plants and genetic diversity were correlated with each other, and both showed a positive relationship with landscape age. Plot species richness showed differing responses for vascular plants, bryophytes and lichens. At this finer scale, the richness of vascular plants was not significantly related to landscape age, which had a small effect size compared to the models of bryophyte and lichen richness. MAIN CONCLUSION: Our study suggests that imprints of past glaciations in Arctic vegetation diversity patterns at the regional scale are still detectable today. Since Arctic vegetation is still limited by post‐glacial migration lag, it will most probably also exhibit lags in response to current and future climate change. Our results also suggest that local species richness at the plot scale is more determined by local habitat factors.

The French Military Health Service has standardized its military prehospital care policy in a ''Sauvetage au Combat'' (SC) program (Forward Combat Casualty Care). A major part of the SC training program relies on simulations, which are challenging and costly when dealing with more than 80,000 soldiers. In 2014, the French Military Health Service decided to develop and deploy 3D-SC1, a serious game (SG) intended to train and assess soldiers managing the early steps of SC. The purpose of this paper is to describe the creation and production of 3D-SC1 and to present its deployment. A group of 10 experts and the Paris Descartes University Medical Simulation Department spin-off, Medusims, coproduced 3D-SC1. Medusims are virtual medical experiences using 3D real-time videogame technology (creation of an environment and avatars in different scenarios) designed for educational purposes (training and assessment) to simulate medical situations. These virtual situations have been created based on real cases and tested on mannequins by experts. Trainees are asked to manage specific situations according to best practices recommended by SC, and receive a score and a personalized feedback regarding their performance. The scenario simulated in the SG is an attack on a patrol of 3 soldiers with an improvised explosive device explosion as a result of which one soldier dies, one soldier is slightly stunned, and the third soldier experiences a leg amputation and other injuries. This scenario was first tested with mannequins in military simulation centers, before being transformed into a virtual 3D real-time scenario using a multi-support, multi-operating system platform, Unity. Processes of gamification and scoring were applied, with 2 levels of difficulty. A personalized debriefing was integrated at the end of the simulations. The design and production of the SG took 9 months. The deployment, performed in 3 months, has reached 84 of 96 (88%) French Army units, with a total of 818 hours of connection in the first 3 months. The development of 3D-SC1 involved a collaborative platform with interdisciplinary actors from the French Health Service, a university, and videogame industry. Training each French soldier with simulation exercises and mannequins is challenging and costly. Implementation of SGs into the training program could offer a unique opportunity at a lower cost to improve training and subsequently the real-time performance of soldiers when managing combat casualties; ideally, these should be combined with physical simulations.