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Plastics are a ubiquitous pollutant in the marine environment. Despite growing concerns, quantitative and qualitative data on microplastics in aquatic and marine environments of Atlantic Canada is just emerging. Surface water plastics were measured and categorized by morphology (thread, microfibre, fragment, foam, film, pellet, and microbead) in two locations in Nova Scotia and one in Newfoundland and Labrador, Canada. All sites within the three locations contained plastic with an average abundance of 9669 items/km

Pleuropulmonary blastoma (PPB) is a very rare pediatric lung disease. It can progress from abnormal epithelial cysts to an aggressive sarcoma with poor survival. PPB is difficult to diagnose as it can be confounded with other cystic lung disorders, such as congenital pulmonary airway malformation (CPAM). PPB is associated with mutations in DICER1 that perturb the microRNA (miRNA) profile in lung. How DICER1 and miRNAs act during PPB pathogenesis remains unsolved. Lung epithelial deletion of the Yin Yang1 (Yy1) gene in mice causes a phenotype mimicking the cystic form of PPB and affects the expression of key regulators of lung development. Similar changes in expression were observed in PPB but not in CPAM lung biopsies, revealing a distinctive PPB molecular signature. Deregulation of molecules promoting epithelial–mesenchymal transition (EMT) was detected in PPB specimens, suggesting that EMT might participate in tumor progression. Changes in miRNA expression also occurred in PPB lung biopsies. miR-125a-3p, a candidate to regulate YY1 expression and lung branching, was abnormally highly expressed in PPB samples. Together, these findings support the concept that reduced expression of YY1, due to the abnormal miRNA profile resulting from DICER1 mutations, contributes to PPB development via its impact on the expression of key lung developmental genes. This article has an associated First Person interview with the joint first authors of the paper., Summary: YY1 contributes to pleuropulmonary blastoma pathogenesis as a downstream target of abnormal epithelial DICER1-cleaved miRNA profile and as a transcriptional regulator of key players of lung development.

Human activities are altering the fundamental geography of biogeochemicals. Yet we lack an understanding of how the spatial patterns in organismal stoichiometry affect biogeochemical processes and the tools to predict the impacts of global changes on biogeochemical processes. In this contribution we develop stoichiometric distribution models (StDMs), which allow us to map spatial structure in resource elemental composition across a landscape and evaluate spatial responses of consumers. We parameterise StDMs for a consumer-resource (moose-white birch) system and demonstrate that we can develop predictive models of resource stoichiometry across a landscape and that such models could improve our predictions of consumer space use. With results from our study system application, we argue that explicit consideration of the spatial patterns in organismal elemental composition may uncover emergent individual, population, community and ecosystem properties that are not revealed at the local extents routinely used in ecological stoichiometry. We discuss perspectives for further developments and application of StDMs to advance three emerging frameworks for spatial ecosystem ecology in an era of global change; meta-ecosystem theory, macroecological stoichiometry and remotely sensed biogeochemistry. Progress on these emerging frameworks will allow for the integration of ecological stoichiometry and individual space use and fitness.

Plastics are not only an environmental concern but also an issue of justice in the Arctic, particularly in Inuit Nunangat (Inuit homelands), as plastics and other contaminants that originate in the south accumulate in the north and have implications for Inuit sovereignty and wellness. This collaborative study finds an average of 0.018 plastics/m2 in surface waters in two sites in the eastern Arctic (Tasiujarjuaq in Nunavut near Iqaluit and southwest Greenland offshore from Qaqortoq and Narsaq). A comparison with other studies shows this abundance of plastics is lesser than abundances reported further north in the Arctic, but greater than adjacent waters further south. However, within and across study areas at similar latitudes, there does not appear to be a significant difference in plastic abundance. Some characteristics of recovered plastics such as morphology and colour support local origins, while others support long range transport. Research moving forward should consider relative scales in spatial trends of plastic abundance. The discussion concludes by reflecting on the methods and findings in terms of their role in Inuit governance and research relationships, including elements of research personnel, permitting, categorization, measurement, and reporting findings. Our goal is to provide insights of where we, as scientists, may choose to intentionally move our scientific work towards reconciliation while we produce knowledge about environmental pollution in Inuit Nunangat and the Arctic broadly.

Global forests are being lost and degraded at an alarming rate; hence ecological restoration becomes an integral component ensuring future forest health. Beneficial effects of restoration will depend on scientifically based practices within an adaptive management framework. On the island of Newfoundland, moose (Alces alces) have become overabundant since their introduction in the early 1900s causing regeneration failure of the balsam fir (Abies balsamea) forest. Intensive selective browsing by moose on this foundation species within naturally insect-generated gaps has created “spruce-moose meadows.” Experimental restoration to support Parks Canada Ecological Integrity targets was implemented in the boreal forest of Terra Nova National Park (Newfoundland, Canada), along a gradient of disturbance from closed canopy forest to large insect-disturbed gaps. Seedling planting was carried out under various ground preparation treatments (field planting, aboveground suppression, and scarification). Seedling performance (survival, growth, and browsing occurrence) was monitored over 2 years and mixed-effects models were constructed to determine seedling responses, which form the template of future forests. Results show minimally positive effects of the ground treatments along the gradient of disturbance, while environmental conditions and seedling individual traits explained the majority of seedling responses. Better growth, lower survival, and higher browsing intensity were observed with increasing forest disturbance, with taller seedlings at planting performing the best. Considering that no substantial biological benefits were detected following ground treatments, which are costly and time-consuming to implement, active restoration in boreal forest can be implemented using standard forestry planting protocols, without any ground preparation, independently of the forest degradation state.

As governments around the world grapple with the challenge of responding to increased plastic pollution, extended producer responsibility (EPR) policy, which shifts the responsibility for waste management of a product to producers, is quickly becoming a cornerstone of legislative approaches to this issue. However, the effectiveness of this policy has never been assessed in terms of reducing plastic marine debris. Understanding if a policy like EPR is having an effect requires collecting and analyzing information before and after a policy is introduced. Using British Columbia, Canada as a case study, we evaluate the influence of an EPR policy for packaging to reduce shoreline pollution. We use available citizen science data to demonstrate that there has been no reduction in pollution levels after the introduction of the policy. The findings also highlight some limitations when using citizen science data for a purpose it was not intended for. To effectively evaluate prevention of plastic pollution in the marine environment, plastic policy interventions require monitoring programs tailored to their specific requirements.

Legibility is the extent to which a space can be easily recognized. Evaluating legibility is particularly desirable in indoor spaces, since it has a large impact on human behavior and the efficiency of space utilization. However, indoor space legibility has only been studied through survey and trivial simulations and lacks reliable quantitative measurement. We utilized a Deep Convolutional Neural Network (DCNN), which is structurally similar to a human perception system, to model legibility in indoor spaces. To implement the modeling of legibility for any indoor spaces, we designed an end-to-end processing pipeline from indoor data retrieving to model training to spatial legibility analysis. Although the model performed very well (98% top-1 accuracy) overall, there are still discrepancies in accuracy among different spaces, reflecting legibility differences. To prove the validity of the pipeline, we deployed a survey on Amazon Mechanical Turk, collecting 4,015 samples. The human samples showed a similar behavior pattern and mechanism as the DCNN models. Further, we used model results to visually explain legibility in different architectural programs, building age, building style, visual clusterings of spaces and visual explanations for building age and architectural functions., 20 pages, 19 figures, 7 tables

This study reports the first baselines of plastic ingestion for three fish species that are common food fish in Newfoundland, Canada. Species collections occurred between 2015-2016 for Atlantic cod (Gadus morhua), Atlantic salmon (Salmo salar), and capelin (Mallotus villosus). The frequency of occurrence (%FO) of plastic ingestion for both spawning Atlantic salmon (n=69) and capelin (n=350) was 0%. Of the 1,010 Atlantic cod collected over two years, 17 individuals had ingested plastics, a %FO of 1.68%. This is the only multi-year investigation of plastic ingestion in Atlantic cod for the Northwest Atlantic, and the first for capelin and salmon in the region. Considering the ecological, economic, and cultural importance of these fish species, this study is the beginning of a longitudinal study of plastic ingestion to detect future changes in contamination levels.HighlightsIngestion rate (%FO) of plastics in Atlantic cod is 1.68%Ingestion rate (%FO) of plastics in Atlantic salmon and capelin is 0%First study of plastic ingestion rates in Atlantic salmon and capelinMulti-year baseline of plastic ingestion in Atlantic cod in the Northwest AtlanticPlastic ingestion rates for three food fish species in Newfoundland, Canada, are lowTermsFrequency of occurrence (%FO): the number of individuals in a population or group that have ingested plastics (not indicative of the number of particles ingested per individual)

Selection of high priority sites for ecological restoration becomes essential with globally decreasing forest cover following natural and anthropogenic disturbances. A disturbance gradient resulting from native insect ( Choristoneura fumiferana ) outbreaks and non-native moose ( Alces alces ) browsing was studied in balsam fir forest stands in Newfoundland (Canada) to inform land managers where active vs . passive restoration would be most appropriate. The disturbance gradient ranged from small gaps (area 5 ha, which were dominated by grasses, early succession forbs and had abiotic conditions closer to early succession boreal forest, indicating an ecological threshold had been crossed, confirming the need for active restoration. To allow regeneration regardless of gap size, reduction of moose numbers must be continued. Threshold identification in the boreal forest should be based on disturbance regime and used to inform critical areas for future forest restoration strategies. Based on our study, insect outbreak areas >5 ha should be prioritized for active restoration, as the crossing of a biotic threshold indicates that such sites cannot naturally return to pre-disturbance balsam fir forests.

Many typical neuston trawls can only be used during relatively calm sea states and slow tow speeds. During two expeditions to the Bay of Bengal and the eastern South Pacific we investigated whether the new, high-speed AVANI trawl (All-purpose Velocity Accelerated Net Instrument) collects similar amounts and types of microplastics as two established scientific trawl designs, the manta trawl and the DiSalvo neuston net. Using a 335 μm net, the AVANI trawl can collect microplastics from the sea surface at speeds up to 8 knots as it “skis” across the surface, whereas the manta and DiSalvo neuston trawls must be towed slowly in a less turbulent sea state and often represent shorter tow lengths. Generally, the AVANI trawl collected a greater numerical abundance and weight of plastic particles in most size classes and debris types than the manta trawl and DiSalvo neuston net, likely because these trawls only skim the surface layer while the AVANI trawl, moving vertically in a random fashion, collects a “deeper” sample, capturing the few plastics that float slightly lower in the water column. However, the samples did not differ enough that results were significantly affected, suggesting that studies done with these different trawls are comparable. The advantage of the AVANI trawl over traditional research trawls is that it allows for collection on vessels underway at high speeds and during long transits, allowing for a nearly continuous sampling effort over long distances. As local surface currents make sea surface abundance widely heterogeneous, widely spaced short-tow trawls, such as the manta and DiSalvo trawls, can catch or miss hotspots or meso-scale variability of microplastic accumulations, whereas the AVANI trawl, if utilized for back-to-back tows of intermediate distances (5–10 km), can bridge variable wind conditions and debris concentrations potentially reducing variance and provide a greater resolution of spatial distribution.

Cet article presente les methodes optiques de mesures dimensionnelles sans contact. Les capteurs utilisant cette methode sont simples et peu couteux, et la methode est donc largement employee dans l'industrie mecanique. Les principes utilises sont abordes dans cet article. Puis des systemes plus complexes, telles que l'episcopie ou la triangulation, permettant notamment des mesures tridimensionnelles, sont presentees.

Cet article presente des methodes optiques tres specifiques pour la mesure dimensionnelle sans contact. Ces methodes ont une mise en œuvre plus complexe que celle des methodes traditionnelles, mais avec un champ d'application un peu different. Ainsi la telemetrie par mesure de temps de vol et l’interferometrie utilisent la vitesse de propagation finie de la lumiere. La telemetrie sert a effectuer des releves dimensionnels sur des pieces de grandes dimensions, par exemple dans le bâtiment. D'autres techniques sont dediees a la mesure de zones difficiles d'acces, de pieces reflechissantes, etc.

Cet article presente des capteurs tres specifiques utilises pour les mesures sans contact. Les technologies abordees sont les comparateurs pneumatiques, les capteurs a ultrasons, a micro-ondes, utilisant des rayonnements ionisants, a force atomique, a effet tunnel et enfin le GPS. Tous ces capteurs offrent des proprietes specifiques qui permettent d'etendre les possibilites de la mesure sans contact. Pour chacune de ces technologies, cet article presente les principes, les caracteristiques techniques et les domaines d'utilisation.

Cet article compare sous forme de tableau toutes les methodes de mesures sans contact. Une premiere comparaison concerne toutes les methodes utilisables pour la mesure des profils, formes, et etats de surface. Puis un second tableau compare les methodes de mesure de deplacement sans contact. Enfin une liste non exhaustive de fournisseurs de ces technologie vient conclure cet article.

Les capteurs magnetiques et capacitifs sont utilises pour mesurer des positions ou des deplacements de faibles ou de moyennes amplitudes (de la fraction de micrometre a 50 mm). Des realisations speciales permettent d'obtenir des resolutions de l'ordre du nanometre. L'encombrement de ces capteurs est generalement faible et ils peuvent etre adaptes pour fonctionner dans des conditions de temperature et de pression difficiles. Des grandes bandes passantes sont obtenues avec des principes de mesures n'utilisant pas de frequence porteuse. Cet article s'insere dans une serie consacree aux capteurs de mesures dimensionnelles sans contact : - Mesures sans contact. Generalites [R 1 330]; - Mesures sans contact. Methodes magnetiques et capacitives [R 1 331]; - Mesures sans contact. Methodes optiques (partie 1) [R 1 332]; - Mesures sans contact. Methodes optiques (partie 2) [R 1 333]; - Mesures sans contact. Autres methodes [R 1 334]; - Mesures sans contact. Comparatif [Comp. R 1 335]. Le lecteur consultera utilement les articles Controle dimensionnel en production de serie [R 1 305] et Capteurs de deplacement [R 1 800] dans ce traite.