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Introduction: This research explores the application of generative artificial intelligence, specifically the novel ARISGAN framework, for generating highresolution synthetic satellite imagery in the challenging arctic environment. Realistic and high-resolution surface imagery in the Arctic is crucial for applications ranging from satellite retrieval systems to the wellbeing and safety of Inuit populations relying on detailed surface observations. Methods: The ARISGAN framework was designed by combining dense block, multireceptive field, and Pix2Pix architecture. This innovative combination aims to address the need for high-quality imagery and improve upon existing state-of-the-art models. Various tasks and metrics were employed to evaluate the performance of ARISGAN, with particular attention to land-based and sea icebased imagery. Results: The results demonstrate that the ARISGAN framework surpasses existing state-of-the-art models across diverse tasks and metrics. Specifically, land-based imagery super-resolution exhibits superior metrics compared to sea ice-based imagery when evaluated across multiple models. These findings confirm the ARISGAN framework's effectiveness in generating perceptually valid highresolution arctic surface imagery. Discussion: This study contributes to the advancement of Earth Observation in polar regions by introducing a framework that combines advanced image processing techniques with a well-designed architecture. The ARISGAN framework's ability to outperform existing models underscores its potential. Identified limitations include challenges in temporal synchronicity, multispectral image analysis, preprocessing, and quality metrics. The discussion also highlights potential avenues for future research, encouraging further refinement of the ARISGAN framework to enhance the quality and availability of high-resolution satellite imagery in the Arctic. [ABSTRACT FROM AUTHOR]

Introduction: This research explores the application of generative artificial intelligence, specifically the novel ARISGAN framework, for generating high-resolution synthetic satellite imagery in the challenging arctic environment. Realistic and high-resolution surface imagery in the Arctic is crucial for applications ranging from satellite retrieval systems to the wellbeing and safety of Inuit populations relying on detailed surface observations.Methods: The ARISGAN framework was designed by combining dense block, multireceptive field, and Pix2Pix architecture. This innovative combination aims to address the need for high-quality imagery and improve upon existing state-of-the-art models. Various tasks and metrics were employed to evaluate the performance of ARISGAN, with particular attention to land-based and sea ice-based imagery.Results: The results demonstrate that the ARISGAN framework surpasses existing state-of-the-art models across diverse tasks and metrics. Specifically, land-based imagery super-resolution exhibits superior metrics compared to sea ice-based imagery when evaluated across multiple models. These findings confirm the ARISGAN framework’s effectiveness in generating perceptually valid high-resolution arctic surface imagery.Discussion: This study contributes to the advancement of Earth Observation in polar regions by introducing a framework that combines advanced image processing techniques with a well-designed architecture. The ARISGAN framework’s ability to outperform existing models underscores its potential. Identified limitations include challenges in temporal synchronicity, multi-spectral image analysis, preprocessing, and quality metrics. The discussion also highlights potential avenues for future research, encouraging further refinement of the ARISGAN framework to enhance the quality and availability of high-resolution satellite imagery in the Arctic.

This paper focuses on the environmental challenges related to the future development of the Northern Sea Route (NSR). With special reference to the Sino-Russian cooperation, this article assumes the opportunity for Russia to develop its Arctic zone with new infrastructure by taking advantage of the opening of the NSR as a future extension of the Chinese Belt and Road Initiative (BRI). However, the increasing shipping activities in the Arctic waters raise much concern regarding the vulnerability of the Arctic environment. The article concludes that a more environmentally conscious approach to the economic enhancement of the NSR is highly recommended.

With the increasing melting of Arctic sea ice, the importance of studying Arctic issues is becoming more and more prominent. By using ScienceDirect database as the main search scope, the authors systematically combed foreign literature on Arctic issues from 2007 to 2021, and analyzed the research status of foreign Arctic issues from four aspects: Arctic routing, economy, politics and environment. It was concluded that the future research on Arctic routing would focus on the operation mode; The research on Arctic economic issues would focus on regional economy and industry development; The research on Arctic politics would still focus on how to cooperate in the governance of the Arctic. Although there will be more qualitative and descriptive analyses in current research on Arctic politics, quantitative analysis and theoretical innovation would be increased in the future; Research on Arctic environmental issues will focus on the balance between economic development and environmental protection in the Arctic, and further pay attention to the sustainable development of the Arctic.

Objective: This study aimed to provide the first data on the occurrence of thyroid autoimmunity among Inuit in Greenland, a distinct ethnic group who is not iodine deficient. Design: This study is a population-based cross-sectional study. Methods: Data were collected in Nuuk in West Greenland and in Ammassali k district in East Greenland. Information on lifestyle, diet and diseases was obtained using questionnaires. Thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb) and thyroid-stimulating hormone (TSH) were measured in serum. Iodin e and creatinine were measured in spot urine samples. Results: The participation rate was 95% with 434 Inuit participants; 75 % were smokers. Iodine excretion was 169 μg/24 h in urban West Greenland, 224 μ g/24 h in the main town and 228 μg/24 h in settlements in rural East Greenland. TP OAb, TgAb or either of these was measured in the serum from 3.7, 5.9 and 8.3% of parti cipants, respectively. TPOAb or TgAb was found in 9.3% of Inuit women and 7.5% of men and more frequently, in East Greenland Inuit with the higher iodine excretion ( P = 0.02). There was some evidence suggesting that thyroid autoimmunity was more frequent among non-smokers (12.5%) compared to smokers (7.0%). Harbouring a thyroid autoan tibody was most frequent in participants with TSH above 3.6 mIU/L (P < 0.001). Conclusion: Thyroid autoantibodies were rare among Greenland Inuit. While iodine nutrition was associated with autoimmunity similarly to other e thnic groups, the influence of sex and smoking was limited. This could suggest gen etic component in Inuit, but the impact of cold, selenium and persistent organic pollutants needs to be elucidated.

Understanding the role of temperature in the dynamic response of composite plates is critical for naval systems operating in extreme environments like the Arctic. Despite the advantages of composite materials in improving corrosion resistance and enabling the customization of material properties to their environment, their behavior at cold temperature, especially under dynamic loading, remains elusive. This research gap hinders the effective use of composite materials in extreme environments. Here, we study the dynamic response of air-backed fiberglass epoxy plates under hydrodynamic loading at room temperature and 4 ∘ C. By employing digital image correlation and particle image velocimetry, we investigated the interplay between fluid–structure interactions and cold temperatures. Our findings reveal the critical role of temperature in shaping the dynamic response of air-backed composites through changes in the stiffness and damping properties. At cold temperature, the plate experiences a larger (smaller) deformation in the initial (latter) phase of the dynamic response. Furthermore, we observed a pronounced coupling between the structural response and the flow physics, with peaks of the hydrodynamic loading synchronized with the peak deflections. Our results underscore the importance of considering temperature in the design of naval systems for extreme environments, providing key insights into fluid–structure interactions at cold temperature. • We perform experiments on air-backed composite plates in a laboratory setting. • We characterize fiberglass epoxy plates at room and low temperature ( 4 ∘ C). • We utilize 3D digital image correlation and planar particle image velocimetry. • Temperature affects the damping, bending stiffness, and thermal pre-stress. • We register a strong coupling between structural dynamics and flow physics. [ABSTRACT FROM AUTHOR]

Extreme weather events are increasing in frequency and intensity across the Arctic, one of the planet’s most rapidly warming regions. Studies from southern latitudes have revealed that the ecological impacts of extreme events on living organisms can be severe and long-lasting, yet data and evidence from within the terrestrial Arctic biome appear underrepresented. By synthesizing a total of 48 research articles, published over the past 25 years, we highlight the occurrence of a wide variety of extreme events throughout the Arctic, with multiple and divergent impacts on local biota. Extreme event impacts were quantified using a myriad of approaches ranging from circumpolar modelling to fine-scale experimental studies. We also identified a research bias towards the quantification of impacts related to a few extreme event types in the same geographic location (e.g. rain-on-snow events in Svalbard). Moreover, research investigating extreme event impacts on the ecology of arthropods and especially freshwater biota were scant, highlighting important knowledge gaps. While current data allow for hypotheses development, many uncertainties about the long-term consequences of extreme events to Arctic ecosystems remain. To advance extreme event research in the terrestrial Arctic biome, we suggest that future studies i) objectively define what is extreme in terms of events and ecological impacts using long-term monitoring data, ii) move beyond single-impact studies and single spatial scales of observation by taking advantage of pan-Arctic science-based monitoring networks and iii) consider predictive and mechanistic modelling to estimate ecosystem-level impacts and recovery.

• CFRP/GFRP stacking configurations are used to hybridize face sheets. • CFRP face sheet becomes extremely brittle at low temperatures. • Hybridization is observed to improve the impact resistance at low temperatures. • Dissimilar fiber interfaces cause more delamination during low velocity impact. • Achieving pseudo-ductility of face sheet by hybridization is temperature dependent. In this study, the impact response and damage mechanisms of carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) hybrid face sheet sandwich composites are investigated with the aim to provide an understanding and solution to mitigate the coupling effects of low temperature and low velocity impact damage. Hybridization of face sheet is achieved by stacking CFRP and GFRP in different thickness configurations. Samples are subjected to low-velocity impact at 23 °C and −70 °C to compare and understand the effect of cold temperature in the Arctic environment. Results show that hybridization improves the impact performance at −70 °C. CFRP layers and foam core become extremely brittle at low temperature, but GFRP layers maintain a certain extent of ductility and enhanced laminate strength at low temperature. Moreover, different damage modes (delamination, fiber breakage, core crushing, core shear, face sheet debonding, back face fiber splitting) are observed and characterized by X-ray micro-computed tomography. The additions of GFRP layers to CFRP face sheet mitigated the increased brittle fiber failure observed at low temperatures, however the impact characteristics and damage size was found to be dependent on the hybridization configuration. [ABSTRACT FROM AUTHOR]

The biogeochemical role of zooplankton in the ocean is determined not only by life-long accumulation of chemical elements from the environment, but also by post-mortal transformation of carcasses chemical composition. The contribution of zooplankton carcasses to vertical flux of major and trace elements depends on sedimentation and remineralization rates of detrital particles. Carcasses decomposition rate during sinking from the upper to the deeper water layers determines the rapid recycling of chemical elements and depends on ambient temperature and microbial activity. This data set summarizes 21-day experiment in microcosms that simulates temperature conditions in the Arctic environment. The data show slow decomposition of copepod carcasses compared with initial material on days 14–21 of the experiment. In addition to visual evidence, we provide data on changes in bacterial abundance and biomass during the whole experimental period.

Biocrusts can be found in a wide array of habitats, where they provide important ecosystem services. These microbial associations are particularly important in High Arctic environments, where biocrust colonize the newly exposed barren soil after glacier retreat and significantly contribute to soil stabilization and nutrient cycling. Starting from incipient, structurally simple biolayers, they develop in complexity, increasing from the glacier terminus. Starting from a simple community structure, mainly constituted by cyanobacteria, heterotrophic bacteria and fungi immersed in a self-secreted extracellular polymeric matrix (cyanobacterial crusts), they later may recruit mosses and lichens (moss crusts and lichen crusts, respectively). The extracellular polymeric matrix protects the biocrust community from abiotic constraints, notably drought and freezing stress, from external physical harming factors, and from predation. The physicochemical characteristics of the extracellular matrix are related to several of its properties, such as its soil-stabilizing effect and water retention. We analysed the chemical (monosaccharidic composition) and macromolecular (molecular weight distribution) properties of the extracellular polymeric matrix of biocrusts with different morphologies collected in northwestern Spitsbergen, Norway. The uronic acid content and molecular weight (MW) distribution of the extracellular polysaccharidic matrices (EPMs) appeared in accordance with the developmental stages of the biocrusts. The MW distribution also showed significant differences between the samples, possibly reflecting differences in microbial enzymatic activities leading to the degradation of high-MW polymers into smaller compounds. The MW distribution profiles presented some important differences, reflecting differences in environmental conditions and, probably, the seasonal variance in microbial community composition that is known to characterize the environment examined in the present study. [ABSTRACT FROM AUTHOR]

The greatest change resulting from the Arctic thaw is the activation of Arctic resource development and the development of Arctic ports. In this regard, Arctic governance and Arctic regimes arising from climate change, global warming, resource development, Arctic Route, logistics, maritime boundary delimitation, environmental and biodiversity conservation and sustainable development are underway, and the activities of the Arctic Council (AC). Russia is now investing funds in a comprehensive approach to the collection of information on waterways, hydro-meteorology and maps and the strengthening of safety measures for the prevention of oil spills. In light of this, Russia has proceeded with long-term use and development of the Northern Sea Route despite the constraints of the Arctic environment and conditions. It is also calling for government cooperation with business entities in the development of a nuclear-powered icebreaker fleet. In particular, Russia has played the most active role in Arctic development such as resource development and military base construction with a focus on icebreakers. In this context, the main purpose of this article is to examine sustainable Arctic development policies focusing on the characteristics of Arctic policies and the status of Arctic ports and railway and road networks under Vladimir Putin's presidency. [ABSTRACT FROM AUTHOR]

The urgency of applying effective legal strategies to respond to environmental change in the Arctic is ever more apparent. The existing framework for environmental governance has matured and its constituents are numerous, and many are promising. However, policymakers and other stakeholders contend that new approaches to confronting environmental conditions, including mitigation of climate change and adapting to it, are needed. Many ideas have been offered; they range considerably in their assessment of what changes are needed and by when. Here we briefly describe the cluster of constituents of environmental governance, the international environmental regime, of the Arctic; we briefly note newly recommended approaches; and we analyse two approaches we consider most promising. These, cooperative scientific-based management strategies and adversarial legal actions, are dissimilar – to the point that some policy makers consider them incompatible. We argue, however, that both are needed and we describe elements of their successful use. [ABSTRACT FROM AUTHOR]

Environmental gradients can help us comprehend the range of adaptations or plasticity that a given species can exhibit in response to climatic change. In this study, we assessed the response in female body size, clutch size and egg volume to elevational gradients in closely related wolf spiders. We measured these traits in Pardosa glacialis, P. hyperborea, P. furcifera and P. palustris, collected along elevational gradients across six sites in Arctic and sub-Arctic regions (four sites in Greenland, one in Iceland and one in the Faroe Islands), although not all species were found at all sites. Body size and reproductive traits did not vary with elevation in a consistent manner among species although smaller species were more sensitive to the gradients. The positive relationship between body size and clutch size was most pronounced in the larger species, indicating that larger species are better able to translate favourable environmental conditions into a larger reproductive output. Our study illustrates that elevational gradients may not fully capture spatial variation in environmental conditions experienced by high-latitude wolf spider species. [ABSTRACT FROM AUTHOR]

The Arctic is an important natural laboratory that is extremely sensitive to climatic changes and its monitoring is, therefore, of great importance. Due to the environmental extremes it is often hard to deploy sensors and observations are limited to a few sparse observation points limiting the spatial and temporal coverage of the Arctic measurement. Given these constraints the possibility of deploying a rugged network of low-cost sensors remains an interesting and convenient option. The present work validates for the first time a low-cost sensor array (AIRQino) for monitoring basic meteorological parameters and atmospheric composition in the Arctic (air temperature, relative humidity, particulate matter, and CO2). AIRQino was deployed for one year in the Svalbard archipelago and its outputs compared with reference sensors. Results show good agreement with the reference meteorological parameters (air temperature (T) and relative humidity (RH)) with correlation coefficients above 0.8 and small absolute errors (≈1 °C for temperature and ≈6% for RH). Particulate matter (PM) low-cost sensors show a good linearity (r2 ≈ 0.8) and small absolute errors for both PM2.5 and PM10 (≈1 µg m−3 for PM2.5 and ≈3 µg m−3 for PM10), while overall accuracy is impacted both by the unknown composition of the local aerosol, and by high humidity conditions likely generating hygroscopic effects. CO2 exhibits a satisfying agreement with r2 around 0.70 and an absolute error of ≈23 mg m−3. Overall these results, coupled with an excellent data coverage and scarce need of maintenance make the AIRQino or similar devices integrations an interesting tool for future extended sensor networks also in the Arctic environment.

The NASA Carbon Monitoring System (CMS) and Arctic-Boreal Vulnerability Experiment (ABoVE) have been planned and funded by the NASA Earth Science Division. Both programs have a focus on engaging stakeholders and developing science useful for decision making. The resulting programs have funded significant scientific output and advancements in understanding how satellite remote sensing observations can be used to not just study how the Earth is changing, but also create data products that are of high utility to stakeholders and decisions makers. In this paper we focus on documenting thematic diversity of research themes and methods used, and how the CMS and ABoVE themes are related. We do this through developing a Correlated Topic Model on the 521 papers produced by the two programs and plotting the results in a network diagram. Through analysis of the themes in these papers, we document the relationships between researchers and institutions participating in CMS and ABoVE programs and the benefits from sustained engagement with stakeholders due to recurring funding. We note an absence of policy engagement in the papers and conclude that funded researchers need to be more ambitious and explicit in drawing the connection between their research and carbon policy implications in order to meet the stated goals of the CMS and ABoVE programs.

The Arctic is experiencing substantial increases in human activity in areas ranging from fossil fuel and mineral extraction to transport along Arctic waterways. Such actions may yield new sources of economic benefits and further objectives to promote national defense, yet they may also generate potential risks to the Arctic environment. As such, concerns from various stakeholders have been raised regarding how to make Arctic operations better meet sustainability goals and balance defense and economic objectives with environmental degradation. This article describes how decision analytical tools, such as multicriteria decision analysis (MCDA), may help identify policies and project proposals that minimize the potential for environmental degradation within a framework of maximizing economic, industrial, and defense objectives. Specifically, MCDA conducts value tradeoffs to assess the utility of various decision alternatives against disparate criteria; for this case, this includes the evaluation of Arctic operation sustainability. This article demonstrates through an example of industrial mining in Greenland how MCDA might serve as a tool to guide uncertain decisions for various Arctic projects, and potentially indicate opportunities to structure such projects to provide greater sustainability for their longer-term operations.

This study examined the large inelastic deformation of FH32 grade steel stiffened plates subjected to a low-velocity mass impact. The impact scenario considered is relevant to the operation of marine structures in Arctic environments. Drop-weight impact tests were conducted on specimens with three different geometries at room temperature and −60°C. This paper provides details of the tests for obtaining the quasi-static and rate-dependent mechanical properties of FH32 at room and low temperature, as well as the experimental setup and the testing procedure of the drop-weight impact tests. The experimental results showed that for the tested structures, the crashworthiness was improved significantly at low temperatures, and ductile or brittle fracture was not observed under the testing conditions considered. Numerical simulations of the tests were also performed using several different approaches. In particular, the numerical predictions were more accurate when the rate-dependent plasticity was considered. [ABSTRACT FROM AUTHOR]

We determined, and compared, the abiotic stress state of algae and their attached bacterial communities following their release into the water column during the Arctic sea ice melt season using specific lipid markers that are characteristic of type II photo-oxidation processes, together with those associated with cis-trans isomerase and 10 S -DOX-like lipoxygenase activity, which are indicative of salinity stress. More specifically, parent lipids and some of their oxidation products were quantified in sinking particles (from sediment traps) collected from the Beaufort Sea, Resolute Passage and the Davis Strait (Canadian Arctic) in 2009, 2012 and 2015, respectively. Our data show that salinity- and light-induced bacterial stress processes are temporally decoupled, with the former occurring at the beginning of ice melting and the latter observed during the final stages of ice melt and in subsequent open waters. The salinity-induced bacterial stress seen during the early stages of ice melting contrasts the healthy state of sea ice algae under the same hypersaline conditions. As sea ice melt progresses, brine channels become hyposaline, thus reducing the bacterial salinity stress, while ice algae become susceptible to photodegradation by singlet oxygen ( 1 O 2 ), despite relatively low temperatures and irradiance. However, the presence of high amounts of extracellular polymeric substances (EPS) encapsulating the algae likely prevents the diffusion of 1 O 2 to the attached bacteria. Photo-oxidative stress is enhanced further in open waters due to the low amounts of EPS. The lower amounts of active bacteria in the Arctic compared to temperate or tropical regions is thus attributed to the combined action of efficient salinity stress in spring and photo-oxidative stress in summer. Outcomes from this study also imply that surface sediments from the Canadian Arctic contain relatively high quantities of sea ice-derived organic matter that has undergone a strong degree of salinity-induced stress. [ABSTRACT FROM AUTHOR]

As a key tool for understanding how animals lived in the past, paleopathology informs us about the lives and deaths of fossil animals. We identify paleopathologies within an assemblage of bones of the pachyrostran centrosaurine Pachyrhinosaurus perotorum, an Arctic ceratopsian. More than 1,000 bones of this dinosaur were collected from the Prince Creek Formation of North Slope, Alaska from fossil sites along the Colville River. Our survey shows the occurrence of paleopathology to be very low and comparable to other populations of horned dinosaurs from the lower latitudes, suggesting that the ancient Arctic environment did not impose intense hardships on these dinosaurs greater than in other environments, as expressed by paleopathological modification of the skeleton. This result may be due to the more equable mean annual temperatures in the Arctic region during the Cretaceous. Also of interest, the frequency of occurrence of paleopathology in the Arctic Pachyrhinosaurus population is very low compared to populations of fossil and historic quadrupedal artiodactyls that are recognized as long distance wanderers., (© 2022 American Association for Anatomy.)

Our goal was to examine how the epibenthic invertebrate community in the Pacific Arctic Region might be affected by continued increases in ocean temperatures. We used epibenthic invertebrate catch and bottom temperature data collected on groundfish assessment and ecosystem surveys in the Bering and Chukchi seas from 2009 to 2018 to determine the "preferred" temperature of all taxa. We grouped taxa into five clusters according to their similarity in median temperature and temperature range. We then used an ensemble of eight climate models under Representative Concentration Pathway 8.5 (RCP8.5) scenarios to project bottom temperature from present (2008) to mid-century (2050) and end of the century (2100). Based on these projections, we show how the amount and distribution of cluster-specific thermal habitat might change with ocean warming. We found that by mid-century there was a 50% decrease in thermal habitat for all clusters except for the most eurythermic cluster, and that thermal habitat contracted to the north. By the end of the century there was very little thermal habitat for all clusters, except the most eurythermic cluster, and habitat was further contracted to the north. The cold-water and stenothermic cluster, hypothesized to be the most vulnerable to ocean warming, had virtually no projected thermal habitat by the end of the century. These "losers" were primarily gastropods and the bivalve mussel Musculus sp. These taxa are some of the primary prey to the endangered Pacific walrus (Odobenus rosmarus), which is harvested as a food resource in native Alaskan communities. Bivalves are prey for commercial flatfish such as yellowfin sole (Limanda aspera) and Alaska plaice (Pleuronectes quadrituberculatus). By 2100 the most eurythermic cluster, hypothesized to be the least vulnerable to warming, had projected suitable thermal habitat throughout most of the Bering and Chukchi seas, except nearshore coastal regions. The most abundant species of these "winners" was the basketstar Gorgonocephalus cf. arcticus. The loss of thermal habitat for all but the "winners" could impact the species diversity of the Bering and Chukchi seas because the "winner" cluster accounted for only 26 taxa or 8% of all taxa observed. Although temperature is a key determinant of habitat, a full habitat and ecosystem model is needed to provide more detailed predictions. In addition, more laboratory studies of thermal acclimation potential of Arctic benthic invertebrates are needed. Our results provide the first indications that the epibenthic invertebrate community in the Bering and Chukchi seas, which supports marine mammals, seabirds and human communities, may be seriously impacted by future ocean warming. • By 2100 thermal habitat decreased by 88% for all but the most eurythermic taxa. • Thermal habitat contracted to the north for all but the most eurythermic taxa. • Cold-water, stenothermic taxa ("losers") had virtually no thermal habitat by 2100. • Losers were species that are prey for marine mammals and commercial flatfish. • 92% of taxa were losers, indicating a potential impact of warming on biodiversity. [ABSTRACT FROM AUTHOR]

For indigenous Arctic Canadians, traditional food consumption represents a key source of nutrients and environmental contaminants. Particularly, ingestion of marine mammal blubber and meat may lead to persistent organic pollutant levels and mercury intakes that exceed regulatory thresholds for sensitive populations. We investigated whether temporary adjustments to the consumption of traditional food derived from marine mammals appreciably impacted contaminant exposure and nutrient intakes among indigenous women of childbearing age. Such adjustments can be motivated by the desire to lower contaminant exposure or to increase nutrition, or by the diminishing availability of other traditional food sources. We combined the contaminant fate and transport model GloboPOP with the food chain bioaccumulation model ACC-Human Arctic to simulate polychlorinated biphenyl exposures in female 2007–08 Inuit Health Survey participants. We also calculated daily mercury and nutrient intake rates. Our results suggest that a temporary decrease in marine mammal consumption is largely ineffective at reducing exposure to polychlorinated biphenyls, because of their long elimination half-lives. In contrast, substitution of marine mammals was highly efficient at reducing mercury intake, but also appreciably lowered intakes of iron, manganese, selenium, and ω-3 polyunsaturated fatty acids. The impact of increasing intake of traditional food derived from marine mammals during childbearing age greatly depended on baseline consumption rates; replacement is ill-advised for those who already consume a lot of traditional food due to greater polychlorinated biphenyl and mercury exposures, while replacement was potentially beneficial for those with very limited marine mammal consumption due to increased nutrient intakes. Our calculations primarily suggest that considering baseline traditional food intake rates is critical to devising reproductive dietary adjustment strategies that maximize nutrient intake while minimizing environmental contaminant exposure. [ABSTRACT FROM AUTHOR]

Surface water samples (river and lake) were collected from the Revelva catchment every summer from 2010 to 2013. This study concerns importance of the use of some analytical techniques for pollutants and parameters determination in Arctic environmental samples based on the example of total organic carbon, phenols, and formaldehyde determination and measurement of pH and electrical conductivity parameters. Significant average concentration levels of formaldehyde were observed in 2012 and reached 0.26 mg/dm. Furthermore, the highest determined levels of total organic carbon and electrical conductivity were observed in samples collected in summer 2013. The average value of total organic carbon in that year was 9.54 mg/dm, and electrical conductivity increased to 63.0 µS/cm. The results of surface water samples analyses show an increasing trend in pollutants concentration levels over the years what may suggest that each year the emission of contaminants from lower latitudes is bigger and, consequently, more of them are deposited in the Arctic. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Background Traditional food (TF) consumption represents the main route of persistent organic pollutant (POP) exposure for indigenous Arctic Canadians. Ongoing dietary transitions away from TFs and toward imported foods (IFs) may contribute to decreasing POP exposures observed in these groups. Methods To explore this issue, we combined the global fate and transport model GloboPOP and the human food chain bioaccumulation model ACC-Human Arctic to simulate polychlorinated biphenyl (PCB) exposure in two indigenous Arctic Canadian communities from the Inuvik region, Northwest Territories and Baffin region, Nunavut. Using dietary survey information from initial (1996–98) and follow-up (2005–07) biomonitoring campaigns in Inuvik and Baffin, we simulated PCB exposures (PCB-118, -138, -153, and -180) for each individual study participant and also whole study populations. Results TF intake rates, particularly of marine mammals (MMs), were the most important predictors of modeled PCB exposure, while TF consumption did not associate consistently with measured PCB exposures. Further, reported mean TF intake increased from baseline to follow-up in both Inuvik (from 8 to 183 g d − 1 ) and Baffin (from 60 to 134 g d − 1 ), opposing both the expected dietary transition direction and the observed decrease in human PCB exposures in these communities (ΣPCB Inuvik: from 43 to 29 ng g lipid − 1 , ΣPCB Baffin: from 213 to 82 ng g lipid − 1 ). However dietary questionnaire data are frequently subject to numerous biases (e.g., recall, recency, confirmation), and thus casts doubt on the usefulness of these data. Conclusions Ultimately, our model's capability to reproduce historic PCB exposure data in these two groups was highly sensitive to TF intake, further underscoring the importance of accurate TF consumption reporting, and clarification of the role of dietary transitions in future POP biomonitoring of indigenous Arctic populations. [ABSTRACT FROM AUTHOR]

Ships and offshore platforms that operate in Arctic regions at low temperatures are likely subjected to impact loads that arise from collisions with icebergs. The aim of this paper was to examine the nonlinear impact response of steel-plated structures in an Arctic environment. In addition to material tensile tests for characterisation of the mechanical properties of polar-class high-tensile steel of grade DH36, an experimental study was undertaken in a dropped-object test facility on steel-plated structure models under impact loads and at low temperatures equivalent to those in Arctic regions. LS-DYNA nonlinear finite element computations were also performed for the corresponding test models. We conclude that nonlinear finite element analyses are useful in the analysis of the nonlinear impact structural responses involving yielding, crushing and brittle fracture at low temperatures as long as the modelling techniques are adequate. The conclusions and insights developed in this paper should be useful in the safety design of ships and offshore platforms intended for operation in Arctic regions. [ABSTRACT FROM AUTHOR]

The polar regions (Arctic and Antarctic) constitute up to 14% of the biosphere and offer some of the coldest and most arid Earth's environments. Nevertheless several oxygenic phototrophs including some higher plants, mosses, lichens, various algal groups and cyanobacteria, survive that harsh climate and create the base of the trophic relationships in fragile ecosystems of polar environments. Ecosystems in polar regions are characterized by low primary productivity and slow growth rates, therefore they are more vulnerable to disturbance, than those in temperate regions. From this reason, chemical contaminants influencing the growth of photoautotrophic producers might induce serious disorders in the integrity of polar ecosystems. However, for a long time these areas were believed to be free of chemical contamination, and relatively protected from widespread anthropogenic pressure, due their remoteness and extreme climate conditions. Nowadays, there is a growing amount of data that prove that xenobiotics are transported thousands of kilometers by the air and ocean currents and then they are deposed in colder regions and accumulate in many environments, including the habitats of marine and freshwater cyanobacteria. Cyanobacteria (blue green algae), as a natural part of phytoplankton assemblages, are globally distributed, but in high polar ecosystems they represent the dominant primary producers. These microorganisms are continuously exposed to various concentration levels of the compounds that are present in their habitats and act as nourishment or the factors influencing the growth and development of cyanobacteria in other way. The most common group of contaminants in Arctic and Antarctic are persistent organic pollutants (POPs), characterized by durability and resistance to degradation. It is important to determine their concentrations in all phytoplankton species cells and in their environment to get to know the possibility of contaminants to transfer to higher trophic levels, considering however that some strains of microalgae are capable of metabolizing xenobiotics, make them less toxic or even remove them from the environment. [ABSTRACT FROM AUTHOR]

The results of analysis of specific characteristics of the heart rate variability (HRV) regulation in preschool children living under the Arctic high-latitude conditions are presented. The principal ageand gender-specific differences in the HRV regulation have been inferred from the intergroup evaluations of the HRV indicators in boys and girls. A functional developmental delay has been shown in 2.5-year-old girls compared with boys of the same age group. The applied orthostatic test has shown lower reserve capacities in children of the senior group compared with the junior group. It has been shown that the mechanisms of the regulation of cardiac rhythm in girls experience higher strain during orthostasis as compared with boys. The division of children into age groups with an age difference of one year has allowed the detection of the tendency towards basically different responses to functional loads during orthostasis. The mean HRV values characteristic of four- to six-year-old children living in the Arctic are presented. It has been shown that the children living at middle latitudes have a higher adaptive potential compared with the children living in high-latitude Arctic areas. [ABSTRACT FROM AUTHOR]