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The Cockburn Substage readvance marks the last major late-glacial advance of the northeast sector of the Laurentide Ice Sheet on Baffin Island. The causes of this abrupt, late reversal of retreat are still unclear, but greater chronological control may provide some insight. To date, the literature has focused on the large terminal moraines in the region, providing a date of readvance (circa 9.5–8.5 ka cal BP). In Frobisher Bay, the Cockburn Substage readvance and recession onshore are marked by a series of moraines spread over ∼20 km along the inner bay. Acoustic marine mapping reveals five distinct transverse ridges, morphologically suggestive of grounding-zone wedges, and two later fields of DeGeer moraines on the floor of the inner bay. These indicate that the style of ice retreat (beginning no later than 8.5 ka cal BP) changed over time from punctuated recession of a floating ice front (20 km over >680 years, with four pauses) to more regular tidewater ice-front retreat, reaching the head of the bay 900 years or more after withdrawal from the outer Cockburn limit. The established chronology for final recession in the region is based largely on radiocarbon dating of bulk shell samples and single shells of deposit-feeding molluscs, notably Portlandia arctica, affected by old carbon from carbonate-rich sediments. Sedimentary analysis and judicious sampling for 14C dating of glaciomarine and marine facies in seabed sediment cores enables development of a late- and post-glacial lithostratigraphy that indicates final withdrawal of ice from the drainage basin by 7 ka cal BP. [ABSTRACT FROM AUTHOR]

There is a growing need for healthcare providers to effectively communicate with adolescents with type 1 diabetes (T1D). However, past efforts have been ineffective and fail to break from didactic and directive language. There also a need for clear guidance on the process for developing effective messages that healthcare providers can use as educational and motivational materials in clinical practice. This study outlines the steps and reasoning behind using narratives (e.g. first-person testimonials) as an effective message form for T1D management. This process involved theoretical principles, narrative creation based on real stories from young adults who grew up with T1D, and input from healthcare providers at a top-ranked pediatric endocrinology clinic. After message development, eight adolescents with T1D evaluated the messages in semi-structured interviews. The narratives were built upon constructs of social cognitive theory and the health belief model, with overarching themes of feelings upon diagnosis, ongoing challenges, steps to overcome barriers, and long-term outcome expectations. Healthcare providers offered clinical recommendations to be integrated, including increased blood glucose monitoring; open communication with important others about the disease, including friends and healthcare providers; and greater feelings of optimism and T1D acceptance. Adolescents viewed the messages to be realistic, motivational, and potentially effective tools for self-management. This formative research offers a step-by-step approach for developing T1D narratives, a novel way to reach adolescents with motivational messages. This work can act as a model to help address potential barriers facing adolescents and encourage behaviors that promote successful self-management. [ABSTRACT FROM AUTHOR]

Adolescents with type 1 diabetes (T1D) face a variety of challenges in disease management, and many struggle to achieve optimal glycemic control. Health communication through didactic messaging about the importance of self-management is a commonly used strategy for this population, but narratives have been underutilized. The purpose of this study was to determine if narratives would provide a better tool to improve disease management for adolescents overcoming T1D-specific issues. Adolescent ages 12–17 (N = 191) were enrolled in an online experiment and viewed sets of narratives or standard of care messages. Outcomes were broken into three categories: message evaluation, specifically perceived message effectiveness (PME), and positive emotional reactions; beliefs such as self-efficacy, outcome expectations, and stress and burnout perceptions, and behaviors including disease management and interpersonal communication. Narratives did not significantly outperform standard of care messages, but both message types scored high on PME and other outcomes. We conclude that both narrative and didactic formats may offer utility for healthcare providers working with adolescents, in that narratives provide stories that may inspire positive emotions while standard of care messages provide the necessary clinical information needed to set goals for self-management. [ABSTRACT FROM AUTHOR]

Species distribution models are commonly used in the marine environment as management tools. The high cost of collecting marine data for modelling makes them finite, especially in remote locations. Underwater image datasets from multiple surveys were leveraged to model the presence–absence and abundance of Arctic soft-shell clam (Mya spp.) to support the management of a local small-scale fishery in Qikiqtarjuaq, Nunavut, Canada. These models were combined to predict Mya abundance, conditional on presence throughout the study area. Results suggested that water depth was the primary environmental factor limiting Mya habitat suitability, yet seabed topography and substrate characteristics influence their abundance within suitable habitat. Ten-fold cross-validation and spatial leave-one-out cross-validation (LOO CV) were used to assess the accuracy of combined predictions and to test whether this was inflated by the spatial autocorrelation of transect sample data. Results demonstrated that four different measures of predictive accuracy were substantially inflated due to spatial autocorrelation, and the spatial LOO CV results were therefore adopted as the best estimates of performance. [ABSTRACT FROM AUTHOR]

This paper reports Dorset (800 BC-AD 1300) firewood use and selection at the Phillip's Garden site (EeBi-1), northwestern Newfoundland, Canada. Charcoal fragments from five semi-subterranean dwellings and one midden were predominantly fir (Abies sp.) and spruce (Picea sp.). These genera dominate the modern forest, contemporary driftwood accumulations, and the prehistoric tree pollen record for the region. These data suggest that Dorset collected firewood according to the principle of least effort from nearby sources. [ABSTRACT FROM AUTHOR]

This paper reports Dorset (800 BC--AD 1300) firewood use and selection at the Phillip's Garden site (EeBi-1), northwestern Newfoundland, Canada. Charcoal fragments from five semi-subterranean dwellings and one midden were predominantly fir (Abies sp.) and spruce (Picea sp.). These genera dominate the modern forest, contemporary driftwood accumulations, and the prehistoric tree pollen record for the region. These data suggest that Dorset collected firewood according to the principle of least effort from nearby sources. [ABSTRACT FROM AUTHOR]

The Dorset Paleo-Inuit occupied the island of Newfoundland for over 800 years (1990 BP to 1180 BP), producing a unique and identifiable archaeological record. Despite this, our current understanding of this sea-mammal hunting population is essentially based on past analysis of architecture, artefacts, and animal remains. While these data show that the Dorset intensively used sites at different locations through the Arctic and Subarctic, very little information is known regarding their impact on their surroundings and the environment. Our research is based on soil samples collected at the site of Phillip’s Garden, which is considered to be one of the most intensely occupied sites within the Dorset culture’s geographic range. Beetles, which are known to be ecological specialists, were used as a proxy in this research in order to document the composition and fluctuation in vegetation, and environmental change through time at the site. The analysis demonstrates that the Dorset communities of Phillip’s Garden harvested trees, and modified the environment and the flora surrounding their settlement more intensively than previously thought. [ABSTRACT FROM AUTHOR]

Background: Hepatitis B virus (HBV) DNA sequence data from thousands of samples are present in the public sequence databases. No publicly available, up-to-date, multiple sequence alignments, containing full-length and subgenomic fragments per genotype, are available. Such alignments are useful in many analysis applications, including data-mining and phylogenetic analyses. Results: By issuing a query, all HBV sequence data from the GenBank public database was downloaded (67,893 sequences). Full-length and subgenomic sequences, which were genotyped by the submitters (30,852 sequences), were placed into a multiple sequence alignment, for each genotype (genotype A: 5868 sequences, B: 4630, C: 7820, D: 8300, E: 2043, F: 985, G: 189, H: 108, I: 23), according to the results of offline BLAST searches against a custom reference library of full-length sequences. Further curation was performed to improve the alignment. Conclusions: The algorithm described in this paper generates, for each of the nine HBV genotypes, multiple sequence alignments, which contain full-length and subgenomic fragments. The alignments can be updated as new sequences become available in the online public sequence databases. The alignments are available at . [ABSTRACT FROM AUTHOR]

The glaciers of the Torngat Mountains of northern Labrador are the southernmost of the Canadian Arctic and the easternmost of continental North America. Currently, 195 small mountain glaciers cover an area in excess of ~ 24 km 2 , confined mostly to small cirques and upland depressions. Using a combination of field and remote sensing methods this study reconstructs and dates the areal extent of Torngat glaciers at their Neoglacial maximums, enabling the first assessment of regional glacier change over the past several centuries. Mapped glacier paleomargins (n = 165) are compared to current (2005) glaciers and ice masses, showing a 52.5% reduction in glacier area, with at least 11 former glaciers altogether disappearing. Glacier change is spatially homogenous and independent of most geographic and topographic factors; however, glacier elevation and glacier size mitigated total change. Previously established lichen growth stations were revisited, and growth rates recalculated based on ~ 30-year-long records, enabling the construction of locally derived low- and high-altitude lichen growth curves. Using growth rates and in situ lichen measurements, the retreat from maximum Neoglacial moraine extents are suggested to have occurred between A.D. 1581 and 1673. These findings indicate a similar magnitude of post-LIA retreat to mountain glaciers elsewhere, yet a much earlier timing (~ 200 years) of retreat than other glaciers in the eastern Canadian Arctic. Though no definitive answer explaining this discrepancy is presented, evidence suggests that regional climate dynamics and the importance of solar radiation for Torngat glaciers may play an important role in local glacierization. [ABSTRACT FROM AUTHOR]

Recent warm winters have negatively impacted many rural Labrador residents, raising concerns over regional climate change and variability. To better understand these events, the recent temperature record was examined in detail using atmospheric reanalyses and relevant station data. In addition to quantifying seasonal and annual trends, the influence of major climate drivers is explored and their contributions to recent anomalies are estimated. The North Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO) are identified as the dominant sources of variability, with the winter NAO producing the largest and most predictable anomalies. These drivers are associated with decadal-scale variability in the region, including unusually cool conditions from the 1980 s through late 1990 s and a subsequent shift to warmer conditions. Removing the influence of the NAO and other climate drivers greatly reduces the magnitude of recent warm anomalies. However, temperature trends in the residual data are amplified in most seasons, with winter residual trends four times larger than the raw winter data. This suggests that climate change, previously obscured by natural variability, is exerting a significant influence on Labrador. Although climate change likely contributed relatively little to recent extreme events, it is gradually raising the probability of similar future events. Une analyse des dernières tendances climatiques observées et de leur variabilité au Labrador Les hivers chauds des dernières années ont entraîné des effets négatifs sur de nombreux résidents des régions rurales du Labrador et ont suscité des préoccupations sur les changements climatiques et la variabilité au niveau régional. Pour mieux comprendre ces événements, les relevés de température les plus récents ont fait l'objet d'un examen détaillé en tirant parti des réanalyses atmosphériques et des données des stations pertinentes. En plus de quantifier les tendances saisonnières et annuelles, une exploration de l'influence des principaux facteurs climatiques déterminants a été menée au moyen d'une estimation de leurs contributions aux anomalies récentes. Il est établi que l'oscillation nord-atlantique (ONA) et l'oscillation atlantique multi-décennale (OAM) constituent les principales sources de variabilité, et que c'est l'OAN de l'hiver qui est responsable des anomalies les plus importantes et prévisibles. Ces facteurs déterminants vont de pair avec la variabilité décennale dans la région, y compris les conditions anormalement fraîches enregistrées à partir des années 1980 jusqu'à la fin des années 1990, suivi d'un changement abrupt vers des conditions plus clémentes. Écarter l'influence de l'ONA et des autres facteurs climatiques déterminants réduit considérablement l'étendue des anomalies chaudes observées récemment. Il ressort des données résiduelles, une amplification des tendances de la température au cours de la plupart des saisons, avec des tendances hivernales quatre fois plus accentuées que les données de base pour l'hiver. Cela laisse entendre que les changements climatiques, masqués auparavant par la variabilité naturelle, exercent une influence notable sur le Labrador. Bien que les changements climatiques aient vraisemblablement peu contribué aux événements extrêmes récents, ils augmentent peu à peu la probabilité que de tels événements se produisent à l'avenir. [ABSTRACT FROM AUTHOR]

DNA sequence analysis is undertaken in many biological research laboratories. The workflow consists of several steps involving the bioinformatic processing of biological data. We have developed a suite of web-based online bioinformatic tools to assist with processing, analysis and curation of DNA sequence data. Most of these tools are genome-agnostic, with two tools specifically designed for hepatitis B virus sequence data. Tools in the suite are able to process sequence data from Sanger sequencing, ultra-deep amplicon resequencing (pyrosequencing) and chromatograph (trace files), as appropriate. The tools are available online at no cost and are aimed at researchers without specialist technical computer knowledge. The tools can be accessed at http://hvdr.bioinf.wits.ac.za/SmallGenomeTools, and the source code is available online at https://github.com/DrTrevorBell/SmallGenomeTools. [ABSTRACT FROM AUTHOR]

This study presents the first complete glacier inventory of the Torngat Mountains, northern Labrador, Canada. In total, 195 glaciers and ice masses are identified, covering a total area of 24.5±1.8 km2. Mapped ice masses range in size from 0.01 to 1.26 km2, with a median size of 0.08 km2. Ice masses have a median elevation of 776 ma.s.l. and span an altitudinal range of 290-1500 ma.s.l. Indications of ice flow suggest at least 105 active glaciers in the Torngat Mountains. Analysis of morphometric and topographic parameters suggests that the regional distribution of ice masses is linked to physiographic setting while the preservation of coastal ice masses at low elevation is related to local meteorological conditions. In the most coastal environments, ice masses are shown to exist below the regional glaciation level due to topographic shadowing, coastal proximity and widespread debris cover. This study provides a baseline for future change assessment. [ABSTRACT FROM AUTHOR]

Aims: The aims of this study were to develop bioinformatics tools to explore ultra-deep pyrosequencing (UDPS) data, to test these tools, and to use them to determine the optimum error threshold, and to compare results from UDPS and cloning based sequencing (CBS). Methods: Four serum samples, infected with either genotype D or E, from HBeAg-positive and HBeAg-negative patients were randomly selected. UDPS and CBS were used to sequence the basic core promoter/precore region of HBV. Two online bioinformatics tools, the “Deep Threshold Tool” and the “Rosetta Tool” (http://hvdr.bioinf.wits.ac.za/tools/), were built to test and analyze the generated data. Results: A total of 10952 reads were generated by UDPS on the 454 GS Junior platform. In the four samples, substitutions, detected at 0.5% threshold or above, were identified at 39 unique positions, 25 of which were non-synonymous mutations. Sample #2 (HBeAg-negative, genotype D) had substitutions in 26 positions, followed by sample #1 (HBeAg-negative, genotype E) in 12 positions, sample #3 (HBeAg-positive, genotype D) in 7 positions and sample #4 (HBeAg-positive, genotype E) in only four positions. The ratio of nucleotide substitutions between isolates from HBeAg-negative and HBeAg-positive patients was 3.5∶1. Compared to genotype E isolates, genotype D isolates showed greater variation in the X, basic core promoter/precore and core regions. Only 18 of the 39 positions identified by UDPS were detected by CBS, which detected 14 of the 25 non-synonymous mutations detected by UDPS. Conclusion: UDPS data should be approached with caution. Appropriate curation of read data is required prior to analysis, in order to clean the data and eliminate artefacts. CBS detected fewer than 50% of the substitutions detected by UDPS. Furthermore it is important that the appropriate consensus (reference) sequence is used in order to identify variants correctly. [ABSTRACT FROM AUTHOR]

Drawing on vulnerability approaches from the climate change literature, this paper explores the vulnerability of residents of the community of Rigolet, Nunatsiavut, Labrador, to changes in freshwater. Our approach emphasizes local preferences and values. We analyze the results from 89 household interviews (88% response) and targeted interviews in Rigolet to consider the human experience of climate variability and change. Residents report that changes in the spatial and temporal distribution of freshwater are currently challenging their ability to access preferred drinking water and food sources and are adding to the financial barriers that restrict their time spent on the land. The results of our study suggest that Rigolet residents are successfully adapting to existing freshwater changes in their watershed, though these adaptations have not come without sacrifice. The adaptive capacity of Rigolet residents has been supported by resource flexibility and experience-based knowledge of freshwater variability within their watershed, among other factors. Findings suggest that the exposure of sub-Arctic and Arctic communities to freshwater changes and their capacity to adapt are largely shaped by the lifeways of residents and the manner and degree to which they are dependent on local freshwater systems. [ABSTRACT FROM AUTHOR]

Background: An online tool, which extracts and summarises nucleotide or amino acid sequence data at specified loci of interest, was developed and tested using the basic core promoter/precore (BCP/PC) region of the hepatitis B virus (HBV). The tool is aimed at researchers without specialist computer skills. Methods: The tool consists of a web-based front-end, with a CGI script, which runs Python code to generate an output web-page. The Python code searches the input sequence data for a specified anchor motif, after which it generates summary tables and graphs of residue and motif distributions. Results: After the user provides an input file in FASTA format containing aligned sequence data (nucleotides or amino acids) and specifies an anchor motif at a known coordinate, the tool summarizes the nucleotides or amino acids at the specified loci, their frequency and analyzes motif patterns of the loci.The tool can output a graph that displays the frequency of mutations relative to a reference sequence. The tool was used to analyze the BCP/PC region of HBV belonging to subgenotypes A1, A2 and subgenotype D and to serotype HBV. The "Discovery Mode" ignores conserved loci and assists in identifying potential loci of interest. Conclusions: Although HBV was used to demonstrate the utility of the Mutation Reporter Tool, the tool has wide application as it is genome-agnostic: nucleotide or amino acid sequence data from any organism can be processed. Rapid characterisation of many sequences can be achieved easily when the loci of interest are known. The tool is available online, without charge, at http://hvdr.bioinf.wits.ac.za/tools. [ABSTRACT FROM AUTHOR]

Abstract: Present-day sediment distribution offers a potentially strong constraint on past ice sheet evolution. Glacial system models (GSMs), however, cannot address this constraint while lacking appropriate representations of subglacial sediment production and transport. Incorporating these elements in GSMs is also required in order to quantify the impact of a changing sediment cover on glacial cycle dynamics. Towards these goals, we present a subglacial process model (hereafter referred to as the sediment model) that incorporates mechanisms for sediment production, entrainment, transport, and deposition. Bedrock erosion is calculated by both Hallet''s and Boulton''s abrasion laws separately, and by a novel quarrying law parametrized as a function of subglacial cavity extent. These process-oriented erosion laws are compared against a simple empirical relationship between erosion rate and the work done by basal stress. Sediment entrainment is represented by Philip''s law for regelation intrusion and soft-bed deformation is included as a subglacial sediment transport mechanism. The model is driven by the data-calibrated MUN (3D) GSM and a newly developed subglacial hydrology module. The sediment model is applied to the last North American glacial cycle and predicts sediment thickness and cumulative erosion patterns. Results are obtained in the context of a sensitivity analysis and are compared against the present-day distribution of glacigenic sediment and geological estimates of Laurentide Ice Sheet erosion. Given plausible ranges for the sensitivity parameters, chosen a priori based on available literature or on heuristic arguments, the calculated erosion depths overlap with the geological estimates of Laurentide erosion. Most of the runs in the sensitivity set produce unrealistically thick and continuous moraines along the eastern, southern and western margins of the North American ice complex, which suggests that the model overestimates sediment entrainment and thus englacial transport. A realistic sediment distribution is only obtained when the entrainment rate is capped at the average basal melting rate, which suggests that modelled entrainment and basal melting rates should be of the same order of magnitude. [Copyright &y& Elsevier]

While PCR amplicons extend to a few thousand bases, the length of sequences from direct Sanger sequencing is limited to 500-800 nucleotides. Therefore, several fragments may be required to cover an amplicon, a gene or an entire genome. These fragments are typically sequenced in an overlapping fashion and assembled by manually sliding and aligning the sequences visually. This is time-consuming, repetitive and error-prone, and further complicated by circular genomes. An online tool merging two to twelve long overlapping sequence fragments was developed. Either chromatograms or FASTA files are submitted to the tool, which trims poor quality ends of chromatograms according to user-specified parameters. Fragments are assembled into a single sequence by repeatedly calling the EMBOSS merger tool in a consecutive manner. Output includes the number of trimmed nucleotides, details of each merge, and an optional alignment to a reference sequence. The final merge sequence is displayed and can be downloaded in FASTA format. All output files can be downloaded as a ZIP archive. This tool allows for easy and automated assembly of overlapping sequences and is aimed at researchers without specialist computer skills. The tool is genome- and organism-agnostic and has been developed using hepatitis B virus sequence data. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) share transmission routes and are endemic in sub-Saharan Africa. The objective of the present study was to use the Taormina definition of occult HBV infection, together with stringent amplification conditions, to determine the prevalence and characteristics of HBV infection in antiretroviral treatment (ART)-naïve HIV+ve adults in a rural cohort in South Africa. The presence of HBV serological markers was determined by enzyme linked immunoassay (ELISA) tests. HBV DNA-positivity was determined by polymerase chain reaction (PCR) of at least two of three different regions of the HBV genome. HBV viral loads were determined by real-time PCR. Liver fibrosis was determined using the aspartate aminotransferase-to-platelet ratio index. Of the 298 participants, 231 (77.5%) showed at least one HBV marker, with 53.7% HBV DNA-ve (resolved) and 23.8% HBV DNA+ve (current) [8.7% HBsAg+ve: 15.1% HBsAg-ve]. Only the total number of sexual partners distinguished HBV DNA+ve and HBV DNA-ve participants, implicating sexual transmission of HBV and/or HIV. It is plausible that sexual transmission of HBV and/or HIV may result in a new HBV infection, superinfection and re-activation as a consequence of immunesuppression. Three HBsAg-ve HBV DNA+ve participants had HBV viral loads <200 IU/ml and were therefore true occult HBV infections. The majority of HBsAg-ve HBV DNA+ve participants did not differ from HBsAg+ve HBV DNA+ve (overt) participants in terms of HBV viral loads, ALT levels or frequency of liver fibrosis. Close to a quarter of HIV+ve participants were HBV DNA+ve, of which the majority were HBsAg-ve and were only detected using nucleic acid testing. Detection of HBsAg-ve HBV DNA+ve subjects is advisable considering they were clinically indistinguishable from HBsAg+ve HBV DNA+ve individuals and should not be overlooked, especially if lamivudine is included in the ART. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) are hyperendemic in sub-Saharan Africa. The HBV genotypes prevailing in HIV-infected Africans are unknown. Our aim was to determine the HBV genotypes in HIV-infected participants and to identify clinically significant HBV mutations. From 71 HBV DNA+ve HIV-infected participants, 49 basic core promoter/precore (BCP/PC) and 29 complete S regions were successfully sequenced. Following phylogenetic analysis of 29 specimens in the complete S region, 28 belonged to subgenotype A1 and one to D3. Mutations affecting HBeAg expression at the transcriptional (1762T1764A), translational (Kozak 1809-1812, initiation 1814-1816, G1896A with C1858T), or post translational levels (G1862T), were responsible for the high HBeAg-negativity observed. The G1862T mutation occurred only in subgenotype A1 isolates, which were found in one third (7/21) of HBsAg-ve participants, but in none of the 18 HBsAg+ve participants (p<0.05). Pre-S deletion mutants were detected in four HBsAg+ve and one HBsAg-ve participant/s. The following mutations occurred significantly more frequently in HBV isolated in this study than in strains of the same cluster of the phylogenetic tree: ps1F25L, ps1V88L/A; ps2Q10R, ps2 R48K/T, ps2A53V and sQ129R/H, sQ164A/V/G/D, sV168A and sS174N (p<0.05). ps1I48V/T occurred more frequently in females than males (p<0.05). Isolates with sV168A occurred more frequently in participants with viral loads >200 IU per ml (p<0.05) and only sS174N occurred more frequently in HBsAg-ve than in HBsAg+ve individuals (p<0.05). Prior to initiation of ART, ten percent, 3 of 29 isolates sequenced, had drug resistance mutations rtV173L, rtL180M+rtM204V and rtV214A, respectively. This study has provided important information on the molecular characteristics of HBV in HIV-infected southern Africans prior to ART initiation, which has important clinical relevance in the management of HBV/HIV co-infection in our unique setting. [ABSTRACT FROM AUTHOR]

The surface soil concentrations (n = 997) of ten metals with Canadian Council of Ministers of the Environment soil quality guidelines were mapped on residential properties in the City of St. John's, Newfoundland and Labrador, Canada. Concentrations of all metals are elevated above background levels, five of the ten metals - As, Ba, Cu, Pb, and Zn - have concentrations above environmental health guidelines in more than 20% of samples, and three metals - As, Pb, and V - exceed human health guidelines in 34 to 47% of samples. Using a contamination index, surface soil was shown to be highly contaminated in the downtown area, primarily on residential properties predating the 1950s. In order of influence, the four metals with the highest contamination factor are Pb, Zn, As, and Cu. Compared to background levels, surface soils are significantly enriched in Pb and Cd, and moderately enriched in Cr, Cu, and Zn. A hierarchical clustering procedure indicated strong statistical relationships between the occurrences of two metal groups across all soil samples. One group - Pb-Zn-Cd - has consistently elevated concentrations in soil sampled adjacent to the exterior walls of buildings, although high values were also recorded in roadside sites and from open spaces on properties. The second group - Cr-Ni-Cu - has minimal to moderately elevated concentrations in all sample locations, though slightly higher concentrations along roadsides. The clusters of metals and their spatial concentration patterns suggest that weathered paint, vehicular emissions, and coal burning were important sources for the main contaminants in sampled soils. Of the three metals (i.e., As, Pb, and V) which significantly exceed human health guidelines, Pb and As pose the greatest potential health risk and require further assessment. It is possible that other cities in the region that share similar urban history and characteristics have a potentially hazardous geochemical landscape. [ABSTRACT FROM AUTHOR]

Coastal archaeological heritage is potentially vulnerable to increased erosion resulting from predicted future sea-level rise and increased storminess. As all sites cannot be protected, it is essential that heritage managers know which sites and landscapes are most at risk so they can prioritize resources and decision-making most effectively. One method of doing so is through desk-based modeling of coastal vulnerability. This article outlines the advantages and limitations of such an approach and demonstrates the application of a desk-based model to case studies from Newfoundland's coast. The rate of future sea-level rise around Newfoundland is complicated by its glacio-isostatic recovery since the last ice age. The first step therefore in this assessment is to combine output from glacio-isostatic adjustment models with appropriate rates of global eustatic sea-level rise. Next, these data are integrated with existing information on coastal characteristics (topography, surficial geology, erosion rates) to assess coastal sensitivity to sea-level rise. Finally, overlay of known archaeological sites identifies those locations at greatest risk from destructive coastal changes. The results demonstrate the effectiveness of such models for regional-scale analyses but caution against the use of low resolution data to generate site-specific predictions. [ABSTRACT FROM AUTHOR]

Residential soil and house dust were collected in St John's to assess the levels of lead exposure and potential human health risk. Although St John's does not have an identified, major point source for lead, nor is it a heavily industrialized or populated city, 51% of all analysed soil samples (n = 1231) exceeded the Canadian Council of Ministers of the Environment (CCME) residential soil lead guideline of 140 ppm, 26% exceeded the 400 ppm United States Environmental Protection Agency (US EPA) guideline for soil in children's play areas, and 9% exceeded the 1200 ppm US EPA guideline for soil outside of play areas. High soil lead concentrations, particularly those above 1200 ppm, are clustered in the older downtown core. Samples located along exterior house walls (dripline) have the highest mean soil lead concentrations, followed by open spaces in yards (ambient) and then roadside sites. Lead in dripline soil samples from older housing stock is sourced to lead-bearing paint. Lead from both dripline and ambient samples on properties developed between the 1940s and 1980s have a mixture of sources including coal ash, paint, and leaded gasoline. Approximately 12% of analysed house dust samples (n = 96) exceeded the US EPA guidelines for lead in indoor dust, all from pre-1950s housing and all associated with dripline soil lead concentrations greater than 900 ppm. Human health risk predictions suggest that, although the wider St John's community may not be at risk of adverse health effects, children living in pre-1970s housing may be exposed to increased risk. [ABSTRACT FROM AUTHOR]

This study investigates whether raised beach sequences preserved on emergent coasts of the central Canadian Arctic Archipelago contain a proxy record of past sea-ice conditions and wave intensity. We hypothesize that periods of reduced sea ice (increased open water) expose shorelines to more prolonged and higher wave energy, leading to better-developed beach ridges. Surveys of raised beach sequences on Lowther Island revealed the following patterns: a) high, wide, single- to multi-crested barriers backed by deep swales or lagoons characterize both the active and lowest relict shorelines; b) small, narrow, discontinuous ridges of poorly sorted gravel extend from 1.0 to 7.5 m asl, except from 4.5 to 5.0 m asl; c) ridge morphology is similar to the active and first relict ridges between 7.5 and 11 m asl; d) a near-featureless zone with minor terraces and ridges above 11 m extends to above 30 m asl. These distinct morphological and sedimentary units are interpreted as a function of wave climate and thus of summer sea-ice conditions. This model suggests periods of greater wave activity from the present day back about 500 14C years (530 cal BP; Unit A), during a short interval from 1750 to 1600 14C years BP (1750-1450 cal BP; Unit B'), and earlier from 2900 to 2300 14C years BP (3030-2340 cal BP; Unit C). Units B and D are interpreted as the result of more severe ice conditions with lower wave energy from 2300 to 500 14C years BP (2340-530 cal BP) and earlier from more than 5750 to 2900 14C years BP (6540-3030 cal BP). Discrepancies with previously published interpretations of regional sea-ice history may reflect the local nature of the beach proxy record, which implies occurrences of extensive open-water fetch east and west of Lowther Island but cannot be extrapolated to a regional scale. The beach record shows distinct variation through time and provides an alternative window on past summer ice extent in central Barrow Strait. [ABSTRACT FROM AUTHOR]

Abstract: Iceland scallop (Chlamys islandica) stocks in the North Atlantic are usually pulse harvested, resulting in boom and bust local landings. We describe an adaptive management strategy for a sustainable harvest of Iceland scallops in Gilbert Bay, a Marine Protected Area (MPA) of coastal Labrador. The current management plan for the MPA closes pristine scallop habitat, a practice that under favourable ocean conditions may lead to local reseeding. The community-based co-management structure for the MPA utilizes the local ecological knowledge of fishermen. Scallop harvesters are participating in research on the present state of the resource. Currently scallops are smaller near the mouth of the bay where fishing effort has been concentrated historically. The cooperation of fishers in enforcing area closures and in monitoring the scallop harvest may lead to a sustainable scallop fishery. [Copyright &y& Elsevier]

This paper presents data from two ponds at Port au Choix, in northwestern Newfoundland, each associated with one or more archaeological sites. Disruptions in vegetation in the ponds and surrounding areas are linked to contemporaneous human activities nearby and comparisons are made between Amerindian and Palaeoeskimo impact patterns. Whereas Amerindian occupations had a major impact on the Field Pond basin, only those Palaeoeskimo activities that took place at or in Bass Pond had an impact on its limnology. This difference is linked to site location preferences, the availability of woodland, and distance of human settlement from the pond. This study contributes to our understanding of the dynamic relationship between hunter-gatherers and their environment. [ABSTRACT FROM AUTHOR]

We argue that variable and complex post-glacial relative sea level (RSL) in Newfoundland is linked to (1) the uneven distribution around the coastline of late Maritime Archaic Indian (MAI) sites (5500-3200 bp ) and (2) the apparent absence of early MAI sites (8000-5500 bp ), despite their presence in nearby southern Labrador. Three post-glacial RSL histories are described for different regions of Newfoundland: continuous emergence (type A), initial emergence followed by submergence (type B) and continuous submergence (type C). In areas characterized by type B or C curves, where the lowstand is greater than 20m water depth, late MAI sites older than 3000 bp are today submerged. In all areas other than those characterized by a type A curve, early MAI sites would be under water. The Northern Peninsula is the only region of Newfoundland described by a type A curve. If early MAI did occupy Newfoundland, we predict where on the Northern Peninsula those sites would be found. [ABSTRACT FROM AUTHOR]

A new relative sea-level curve is presented for St. George's Bay, southwest Newfoundland, based on (i) a revised stratigraphic framework and depositional model for glacial and marine deposits exposed in coastal sections and (ii) 19 new radiocarbon dates on shells from emerged and submerged marine deposits, including fossiliferous diamictons. The data produce a type B sea-level curve, falling steeply from an extrapolated marine limit of 105 m above sea level at 14.0 14C ka BP, passing below modern sea level at ~10.6 14C ka BP, to a lowstand of –25 m at ~9.4 14C ka BP, and rising again close to modern sea level by 5.0 14C ka BP. Marine limits in the northern part of the bay have lower elevations (27–65 m) due to delayed ice retreat of up to 1.2 ka. Between 12.8 and at least 12.3 14C ka BP, glaciofluvial outwash graded to falling sea levels between 27 and 17 m above present throughout the bay, whereas lowstand deltas were constructed in sheltered locations at the outlets of major river systems, when sea level was 25 m below present. Establishment of the sea-level lowstand at ~9.4 14C ka BP is supported by new seismic data and radiocarbon dates from St. George's Bay and also from White Bear Bay on the south coast of Newfoundland. Short-term fluctuations in emergence rates of 1–2 m/century between 12.5 and 9.5 14C ka BP are attributed to variable eustatic sea-level rise, superimposed on a declining local glacio-isostatic adjustment. [ABSTRACT FROM AUTHOR]

Almost sixty years after the initial mapping of extensive Quaternary sediments along the coast of St. George's Bay, Newfoundland, a revised stratigraphic section is presented which identifies five main sediment types (diamicton, mud, sand, gravelly sand, gravel) and their stratigraphical position along 39 km of coastline from Highlands to Flat Bay. Most of the sediments overlying a basal till (St. George's River Drift) are interpreted to have been deposited in an ice-proximal to ice-distal glaciomarine environment by debris flow, underflow, current flow, or suspension settling, and capped by glaciofluvial outwash (Bay St. George Delta). For the most part, sections display a relatively simple deglacial sequence in a shallowing marine to fluvial environment. Where hummocky ridges intersect the coast, however, the sedimentary sequences are more complex and the variability in depositional style is typical of grounding line fans at a tidewater glacier margin. The occurrence of an upper diamicton or coarse gravels (Robinsons Head Drift) was generally observed only in grounding-line fan sequences and is interpreted here in the context of marginal fluctuations of a quasi-stable tidewater glacier, and not necessarily a climatically-induced readvance of a land-based ice margin (Robinsons Head readvance). Radiocarbon dates on marine shells from varied stratigraphic positions and sedimentary units suggest rapid deposition occurred in a glaciomarine environment between 14 and 13 ka BP.Près de soixante ans après la cartographie initiale de sédiments quaternaires largement répandus le long de la côte de la baie St. George, à Terre-Neuve, nous présentons une section stratigraphique révisée qui identifie cinq types principaux de sédiments (diamicton, boue, sable, sable graveleux, gravier) et leurs positions stratigraphiques le long de 39 km de côte, de Highlands à Flat Bay. On croit que la plupart des sédiments qui recouvrent un till de fond (dépôts morainiques de la rivière St. George) ont été déposés dans un environnement glacio-marin, allant de proche à loin de la glace, par des coulées de débris, des sous-écoulements, des écoulements de courants ou la sédimentation des matériaux en suspension, et recouverts d'épandages fluvio-glaciaires (delta de la baie St. George). En grande partie, les sections montrent une séquence de déglaciation relativement simple dans un environnement marin de moins en moins profond jusqu'à un environnement fluvial. Toutefois, là où des crêtes à relief de bosses et de creux rencontrent la côte, les séquences sédimentaires sont plus complexes et la variabilité du style de déposition est typique d'un delta de lignes d'ancrage à la limite d'un glacier de marée. L'occurrence d'un diamicton supérieur ou de graviers grossiers (dépôts morainiques de Robinsons Head) a généralement été observé seulement dans des séquences de delta de lignes d'ancrage et on les interprète ici dans le contexte de fluctuations marginales d'un glacier de marée quasi stable et pas nécessairement d'une réavancée, induite par le climat, d'une marge de glace ancrée sur le terrain (réavancée de Robinsons Head). Des datations au carbone 14 sur des coquillages marins provenant de diverses positions stratigraphiques et d'unités sédimentaires suggèrent qu'une déposition rapide dans un environnement glacio-marin a eu lieu entre 14 et 13 ka BP.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Focuses on the differing degrees of environmental change in the eastern and western parts of northern Canada in the late 20th century. Widespread recognition that human activities are changing the global climate; Warmest year according to the composite instrumental record of average global temperatures since 1860; Meeting of the Canadian Association of Geographers.

Presents a rejoinder to Ben Fine and Zav Rustomjee's remarks about the author's review of their book 'South Africa's political economy: From minerals-energy complex to industrialisation.' Focus on South Africa's mineral-rich character; Notion of the Minerals-Energy Complex.

Presents a reply to the comment given by I. Brookes to the article "Late Wisconsinan stratigraphy and chronology of southern St. George's Bay, Newfoundland: a re-appraisal," by Trevor Bell, David G.E. Liverman, Martin J. Batterson and Kevin Sheppard, which appeared in the 2001 issue of the 'Canadian Journal of Earth Sciences." Disagreements in field observations and interpretations; Discussion of a complex sedimentary sequences of interbedded diamicton, gravel and mud above the basal till; Discounting the significance of a date given to a diamicton at Highlands.

Target audience ratings of the likely impact of persuasive messages, known as perceived message effectiveness (PME), are commonly used in health communication campaigns. However, applications of PME rely on a critical assumption—that is, that PME is a valid indicator of the likely effectiveness of messages. To examine the evidence supporting this assumption, we conducted a systematic review and meta-analysis of longitudinal studies in the tobacco education campaigns literature. Six longitudinal studies examining the predictive validity of PME met inclusion criteria. Results indicated that PME ratings were significantly associated with the majority of outcomes studied. In fact, each of the six studies found PME to be associated with at least one outcome, and across the six studies, PME was associated with message recall, conversations about ads, beliefs about smoking and quitting smoking, quit intentions, and cessation behavior. Meta-analyses demonstrated that PME predicted quit intentions (r =.256, p <.001) and cessation behavior (r =.201, p <.001), revealing effects that were small to medium in magnitude. Our results suggest that PME provides some predictive value as to the likely effectiveness of messages, although additional work using different validation designs, with other health behaviors, and among other populations is needed. [ABSTRACT FROM AUTHOR]

Parents of children with type 1 diabetes (T1D) face uncertainty about the illness. This uncertainty can have negative health consequences for parents and their children. However, little is known about the types of uncertainty associated with T1D diagnosis and subsequent treatment and how this uncertainty is managed. Using uncertainty management theory (UMT) as a framework and 29 in-depth interviews with parents of children with T1D, this study found that parents experienced medical, social, and financial forms of uncertainty. Most parents viewed uncertainty negatively and sought to reduce it by seeking information, joining support groups, and turning to technology. However, some parents preferred uncertainty to the certainty of knowing their child had T1D and, at least initially, chose to maintain uncertainty about the disease by avoiding information. This study also provides practical outcomes that health-care providers can use to help parents of children with T1D reduce and manage uncertainty. [ABSTRACT FROM AUTHOR]

Growing concern about the state of Arctic sea-ice has been highlighted in the recently published ACIA report (2005). The alarming trends of decreasing sea-ice extent and thickness in the Arctic Ocean stress the need for comprehensive studies of past sea-ice variability. The primary goal of this study is to investigate whether raised beach sequences, preserved on the emergent coastline of the central Canadian Arctic, contain a proxy record of past sea-ice intensity. The research approach is to compare variations in beach morphology and sedimentology with a proxy record of sea ice intensity derived from driftwood and whalebone occurrences on emerged beaches. It is hypothesized that periods of reduced sea ice intensity and increased open water would expose shorelines to higher and more prolonged wave energy, leading to better developed beach berms. More specifically then, the study will: a) document variability in beach morphology and sedimentology as a function of age and b) assess the extent to which variations in wave energy between the periods of more or less open water have a recognizable expression in the preserved beaches. Three study sites on Lowther Island, Nunavut, were selected based on a combination of the following characteristics: (1) a well-constrained postglacial emergence history, which allows beach age to be derived from beach elevation; (2) a coastal system that is relatively simple in terms of sediment supply, configuration, and energy regime; (3) coincidence with ongoing modern beach monitoring by the Geological Survey of Canada; and (4) representation of modern sea ice intensity regimes. Methodology includes: remote sensing using airphotos and high-resolution satellite imagery; ground surveys using RTK GPS to map modern and relict beaches; analysis of sediments on beach ridges of varying age; and GIS. Lowther Island has experienced isostatic uplift for more than 9000 yr (9 ka) leading to the development of extensive raised-beach sequences. Preliminary results from three study sites on Lowther Island suggest a regional pattern in raisedbeach morphology. Series of massive and well-developed single-crested beaches are intercalated with numerous and closely spaced beaches of smaller amplitude and often multi-crested. Well-developed beaches are located between 0 and 2, 5 and 7, and 9 and 11 metres of elevation. These elevations correspond to the modern period, 1.25 to 1.75 ka BP and 2.25 to 2.5 ka BP, respectively. These ages do not necessarily correspond to periods of light sea-ice as interpreted from the distribution of driftwood and whalebone. [ABSTRACT FROM AUTHOR]

This study presents the first black spruce, balsam fir and larch tree ring width chronologies from Labrador. It uses a multi-species perspective to study the radial growth response of alpine treeline species in the Mealy Mountains to local and regional climate variables using bootstrapped correlation analysis. The radial growth response of black and white spruce trees is positively sensitive to growing season air temperatures and sea surface temperatures (SSTs) in the vicinity of the Grand Banks. Moisture originating from warm SSTs in the adjacent Labrador Sea appears to affect moisture-sensitive white spruce and balsam fir trees negatively in the Mealy Mountains. Comparative analysis of 4 tree-ring time series indicates that periods of larch sawfly outbreaks have occurred in the Mealy Mountains and that these events exert a significant amount of influence on the radial growth of larch trees in the Mealy Mountains. These inferred periods of insect infestations coincide with others reported in Quebec. Growing season (June-September) temperature is reconstructed for the Mealy Mountains using merged spruce tree ring width chronologies (1847-2004). The reconstruction is in accordance with other reconstructions at regional and hemispheric scales. The sensitivity of spruce trees to local temperature and precipitation is unstable throughout the period of instrumental record due to moisture effects. Further, spruce trees in the Mealy Mountains show evidence of divergence from air temperatures over the last several decades. [ABSTRACT FROM AUTHOR]

Benthic habitat maps, including maps of seabed sediments, have become critical spatial-decision support tools for marine ecological management and conservation. Despite the increasing recognition that environmental variables should be considered at multiple spatial scales, variables used in habitat mapping are often implemented at a single scale. The objective of this study was to evaluate the potential for using environmental variables at multiple scales for modelling and mapping seabed sediments. Sixteen environmental variables were derived from multibeam echosounder data collected near Qikiqtarjuaq, Nunavut, Canada at eight spatial scales ranging from 5 to 275 m, and were tested as predictor variables for modelling seabed sediment distributions. Using grain size data obtained from grab samples, we tested which scales of each predictor variable contributed most to sediment models. Results showed that the default scale was often not the best. Out of 129 potential scale-dependent variables, 11 were selected to model the additive log-ratio of mud and sand at five different scales, and 15 were selected to model the additive log-ratio of gravel and sand, also at five different scales. Boosted Regression Tree models that explained between 46.4 and 56.3% of statistical deviance produced multiscale predictions of mud, sand, and gravel that were correlated with cross-validated test data (Spearman’s ρmud = 0.77, ρsand = 0.71, ρgravel = 0.58). Predictions of individual size fractions were classified to produce a map of seabed sediments that is useful for marine spatial planning. Based on the scale-dependence of variables in this study, we concluded that spatial scale consideration is at least as important as variable selection in seabed mapping. [ABSTRACT FROM AUTHOR]

This paper identifies and characterizes current knowledge on climate change impacts, adaptation, and vulnerability for Canada's northern coastline, outlining key research gaps. Warming temperatures and increased precipitation have been documented across the northern coast, with the rate of sea ice decline ranging from 2.9% to 10.4% per decade. Storm intensity and frequency is increasing, and permafrost is warming across the region. Many of these changes are projected to accelerate in the future, with in excess of 8 °C warming in winter possible under a high-emission scenario by 2081-2100. Vulnerability to these changes differs by region and community, a function of geographic location, nature of climate change impacts, and human factors. Capacity to manage climate change is high in some sectors, such as subsistence harvesting, but is being undermined by long-term societal changes. In other sectors, such as infrastructure and transportation, limitations in climate risk management capacity result in continuing high vulnerabilities. There is evidence that adaptation is taking place in response to experienced and projected impacts, although readiness for adaptation is challenged by limited resources, institutional capacity, and a need for support for adaptation across levels of government. Priority areas for future research include ( i) expanding the sectoral and geographic focus of understanding on climate change impacts, adaptation, and vulnerability; ( ii) integrating climatic and socio-economic projections into vulnerability and adaptation assessments; ( iii) developing an evidence base on adaptation options; and ( iv) monitoring and evaluating the effectiveness of adaptation support. Cross-cutting themes for advancing climate change impacts, adaptation, and vulnerability research on the north coast more broadly include the need for greater emphasis on interdisciplinary approaches and cross-cultural collaborations, support for decision-orientated research, and focus on effective knowledge mobilization. [ABSTRACT FROM AUTHOR]

The Torngat Mountains National Park, northern Labrador, Canada, contains more than 120 small glaciers: the only remaining glaciers in continental northeast North America. These small cirque glaciers exist in a unique topoclimatic setting, experiencing temperate maritime summer conditions yet very cold and dry winters, and may provide insights into the deglaciation dynamics of similar small glaciers in temperate mountain settings. Due to their size and remote location, very little information exists regarding the health of these glaciers. Just a single study has been published on the contemporary glaciology of the Torngat Mountains, focusing on net mass balances from 1981 to 1984. This paper addresses the extent to which glaciologically relevant climate variables have changed in northern Labrador in concert with 20th-century Arctic warming, and how these changes have affected Torngat Mountain glaciers. Field surveys and remote-sensing analyses were used to measure regional glacier area loss of 27% from 1950 to 2005, substantial rates of ice surface thinning (up to 6 m yr-1) and volume losses at Abraham, Hidden, and Minaret glaciers, between 2005 and 2011. Glacier mass balances appear to be controlled by variations in winter precipitation and, increasingly, by strong summer and autumn atmospheric warming since the early 1990s, though further observations are required to fully understand mass balance sensitivities. This study provides the first comprehensive contemporary assessment of Labrador glaciers and will inform both regional impact assessments and syntheses of global glacier mass balance. [ABSTRACT FROM AUTHOR]

This presentation describes the glacial history of Placentia Bay, Newfoundland as interpreted from both seabed and terrestrial glacial records. Multibeam sonar data, augmented by seismic and coring data revealed a range of flow-parallel and flow-transverse glacial landforms on the Placentia Bay seafloor. Flow-parallel landforms identified include drumlins, flutes, megaflutes and crag-and-tails. These landforms show a general trend of convergent flow, interpreted to represent fast-flowing ice which was converging into an ice stream down the axis of Placentia Bay. Flow-parallel landforms and striations from the surrounding land areas demonstrate that the convergent flow can be traced up-ice to regional ice dispersal centres. Flow-transverse landforms include De Geer moraines and grounding-line moraines. De Geer moraines occur in several fields throughout the bay marking the intermittent retreat of grounded ice up the bay. Radiocarbon dates from glaciomarine silt suggest that ice became ungrounded and glaciomarine sedimentation started by at least 16,080 yrs BP. Ice-flow mapping in Placentia Bay also demonstrated that the largely depositional record preserved on the seabed is incomplete, with the apparent absence of a strong westward flow onto the Burin Peninsula. The mostly erosional ice-flow record on land also appears incomplete because there is no evidence to date, for a northeast-southwest ice-flow that is recorded by a fluted field in southwestern Placentia Bay. Given the incomplete records on both the seabed and on land, the integration of seabed data with onshore glacial records provides a better understanding of the glacial history. This integrated approach also represents an important development in mapping palaeoice flows and the understanding of ice sheet behaviour during the transition from largely marine-based to land-based glacial conditions which may reflect the deglacial scenarios in other bays in Newfoundland and elsewhere. [ABSTRACT FROM AUTHOR]

ABSTRACT Landward retreat (marine transgression) is a common response of coastal systems to rising relative sea level. However, given sufficient sediment supply, the coast may advance seaward. The latter response of gravel barriers has been recorded in parts of southeastern and northwestern Canada, where seaward-rising sets of beach ridges are observed in areas of Holocene RSL rise. Cape Charles Yorke, northern Baffin Island, is a 5 km long gravel foreland characterized by seaward-rising beach-ridge crest elevations. The prograded morphology of the Cape Charles Yorke foreland is a prime example of coastal response to a combination of rising RSL and abundant sediment supply, an unusual and little-documented pattern in the Canadian Arctic. The main gravel supply to Cape Charles Yorke is likely from eroding bedrock and raised marine deposits southwest of the foreland. Although not the dominant sediment source, the Cape Charles Yorke delta contributed to the formation of the foreland by sheltering it from easterly storm waves and providing an anchor point for the prograding ridges. The truncation of relict ridges by the modern shoreline suggests a recent regime shift from continuous deposition to predominant erosion. The cause and timing of this shift are unknown but could result from a recent dwindling in sediment supply, increased accommodation space, increased wave energy, and/or an accelerated rise of relative sea level. [ABSTRACT FROM AUTHOR]

Increased variability in weather and sea ice conditions due to climate change has led to high rates of injury, trauma, and death for Inuit travelling on the sea ice. Contributing to these high rates are the ongoing effects of colonial policies that diminish and disrupt the intergenerational transfer of sea ice Inuit Qaujimajatuqangit (IQ). Despite these challenges, place-based experiential IQ continues to be the most important information source for safe travel on the sea ice. This paper presents an Inuit-led, coproduced, cross-cultural research project in which Inuit youth documented and mobilized sea ice IQ in Mittimatalik (Pond Inlet), Nunavut for safe community sea ice travel. We outline the Inuit youth training to facilitate the terminology and participatory mapping workshops and to document this IQ. We also discuss the IQ that was most important to share, and the mapping and artistic methods used to mobilize this IQ into a booklet, maps, and posters. Inuktitut sea ice terms are the foundation to enable youth with the skills to learn about sea ice IQ with experienced hunters. IQ enables Inuit to interpret and synthesize information from weather forecasts, earth observations, and community-based monitoring to apply to local conditions. Seasonal IQ maps of safe and hazardous sea ice conditions provide travel planning information at spatial and temporal scales that supplemental information sources cannot address. The IQ products mobilize preparedness, situational awareness, navigation, and interpretation skills so Inuit youth can become more self-reliant, as access to technology is not always possible once out on the sea ice. [ABSTRACT FROM AUTHOR]

Abstract: Two informally named basins (Mirabilite Basins 1 and 2) along a submergent coastline on Banks Island, Canadian Arctic Archipelago, host up to 1m-thick accumulations of mirabilite (Na2SO4·10H2O) underlying stratified water bodies with basal anoxic brines. Unlike isostatically uplifting coastlines that trap seawater in coastal basins, these basins formed from freshwater lakes that were transgressed by seawater. The depth of the sill that separates the basins from the sea is shallow (1.15m), such that seasonal sea ice formation down to 1.6m isolates the basins from open water exchange through the winter. Freezing of seawater excludes salts, generating dense brines that sink to the basin bottom. Progressive freezing increases salinity of residual brines to the point of mirabilite saturation, and as a result sedimentary deposits of mirabilite accumulate on the basin floors. Brine formation also leads to density stratification and bottom water anoxia. We propose a model whereby summer melt of the ice cover forms a temporary freshwater lens, and rather than mixing with the underlying brines, it is exchanged with seawater once the ice plug that separates the basins from the open sea melts. This permits progressive brine development and density stratification within the basins. [Copyright &y& Elsevier]

This study assesses the stability of Arctic gravel coasts across a range of timescales, based on field and remote-sensing studies of three coastal sites near Resolute Bay, Nunavut. It considers shore-zone sensitivity to ice, wind, and wave forcing at storm-event and annual timescales within a longer-term context, including coastal emergence resulting from postglacial isostatic uplift partially counteracted by accelerating sea-level rise. Another long-term factor associated with climate change is the potential for increased seasonal depth of thaw in the beachface and nearshore. The coast in this area is ice bound on average for 10 months of the year, but the annual duration of ice cover has decreased over the past 30 years (1979-2009) by 0.95 d/y. A longer open-water season has implications for the number and timing of storm-wave events, with increased probability of storms impacting the coast later in the season when the seasonal thaw layer is approaching maximum thickness. Overall, shoreline progradation surpassed erosion in the Resolute area between 1958 and 2006, reflecting a combination of sediment supply and emergence. The coastal impacts of storms were found to be short lived and not necessarily indicative of longer-term trends. Gravel shorelines can be resilient in the face of intermittent storm impacts, but thresholds of stability in this high-latitude setting are poorly understood. If current trends of rising sea level, increasing open-water duration, and more frequent effective wave events continue, there is a heightened potential for more rapid coastal change in the region. [ABSTRACT FROM AUTHOR]

This paper presents an approach that allows production of benthic substrate and habitat maps in fjord environments. This approach is used to support the management of the Gilbert Bay Marine Protected Area (MPA) in southeastern Labrador, Atlantic Canada. Multibeam sonar-derived bathymetry, seabed slope, and acoustic reflectance (backscatter) were combined using supervised classification methods and GIS with ground-truthed benthic sampling in order to derive maps of the substrates and main benthic habitats. Six acoustically distinct substrate types were identified in the fjord, and three additional substrate types without a unique acoustic signature were recognized. Ordination by multidimensional scaling and analysis of similarity generalized these to four acoustically distinct habitat types. Greatest within-habitat (alpha) diversity was found in the coralline-algae encrusted gravel habitat. Greatest between-habitat (beta) diversity was found in the management Zones 1 and 2, which have the highest level of protection. The study confirmed that the zoning plan for the MPA, which was designed to protect spawning and juvenile fish habitat for a local genetically distinct population of Atlantic cod, afforded highest levels of protection to areas with highest habitat diversity. [ABSTRACT FROM AUTHOR]

This paper outlines work currently being undertaken to reconstruct submerged archaeological landscapes off the north coast of Ireland. This research uses the recently-completed Joint Irish Bathymetric Survey (JIBS), which has provided full-coverage high-resolution multibeam bathymetric data for the sea-bed off the north coast. This data has been examined for evidence of past sea-level change and been used to produce palaeo-geographic reconstructions of the past landscape, which in turn have facilitated the identification of ten areas of high archaeological potential. The results presented here will form the basis of a future programme of archaeological survey and prospection. © 2010 The Authors [ABSTRACT FROM AUTHOR]

This paper describes Phase 1 of the project 'Archaeological Applications of the Joint Irish Bathymetric Survey (JIBS) Data', analysing bathymetric and backscatter data derived from multibeam surveys off the north coast of Ireland. In particular, the usability of the data for shipwreck detection, identification and site characterization is explored. In Phase 1, the data was screened for anomalous sea-bed features, which were subsequently described, catalogued and categorized according to their archaeological potential and cross-referenced against existing records. A planned second phase of this project will examine each anomaly in greater detail together with the local and regional hydrodynamic conditions. © 2010 The Authors [ABSTRACT FROM AUTHOR]

Multibeam sonar surveys in the past decade, augmented by single-beam data from the OLEX charting system, reveal landsystems on Atlantic Canadian shelves that are diagnostic of Late Wisconsinan ice-sheet dynamics. Four landsystems are described. (1) The Bay of Fundy landsystem comprises two contrasting sets of bedforms, and is interpreted as evidence of topographically controlled fast-flowing ice adjacent to slower-moving ice. (2) The German Bank landsystem off southwest Nova Scotia is comprised of glacially fluted terrain overprinted by De Geer moraines and arcuate recessional moraines. We infer that a flow of grounded glacial ice out of the Bay of Fundy was followed by steady retreat, punctuated by at least one major re-advance. (3) The Placentia Bay landsystem consists of a convergent field of streamlined landforms with superimposed De Geer moraines, overprinted in one area by flutings. We infer that this landsystem was formed in the onset zone of fast-flowing ice, and that overprinting was due to a re-advance of ice from offshore. (4) The south coast of Newfoundland landsystem, which includes arcuate, fjord-mouth moraines and a coast-parallel, fluted moraine, indicates strong topographic control on a retreating marine ice margin as it reached a fjord coastline. These submarine glacial landsystems are not inconsistent with a conceptual model showing Late Wisconsinan ice advance to shelf edges, rapid calving retreat along deepwater channels and slower retreat of ice margins grounded in shallow water. The re-advances documented two of the study areas have parallels in the Last British Ice Sheet, confirming that the reorganization of marine-based ice sheets, caused by calving in embayments, led to internally forced re-advances. [ABSTRACT FROM AUTHOR]

Differential sea-level change in formerly glaciated areas is predicted owing to variability in extent and timing of glacial coverage. Newfoundland is situated close to the margin of the former Laurentide ice sheet, and the orientation of the shoreline affords the opportunity to investigate variable rates and magnitudes of sea-level change. Analysis of salt-marsh records at four sites around the island yields late Holocene sea-level trends. These trends indicate differential sea-level change in recent millennia. A north–south geographic trend reflects submergence in the south, very slow sea-level rise in the northeast, and a recent transition from falling to rising sea-level at the base of the Northern Peninsula. This variability is best explained as a continued isostatic response to deglaciation. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) is the primary cause of liver-related malignancies worldwide, and there is no effective cure for chronic HBV infection (CHB) currently. Strong immunological responses induced by T cells are associated with HBV clearance during acute infection; however, the repertoire of epitopes (epi) presented by major histocompatibility complexes (MHCs) to elicit these responses in various African populations is not well understood. In silico approaches were used to map and investigate 15-mers HBV peptides restricted to 9 HLA class II alleles with high population coverage in Botswana. Sequences from 44 HBV genotype A and 48 genotype D surface genes (PreS/S) from Botswana were used. Of the 1819 epi bindings predicted, 20.2% were strong binders (SB), and none of the putative epi bind to all the 9 alleles suggesting that multi-epitope, genotype-based, population-based vaccines will be more effective against HBV infections as opposed to previously proposed broad potency epitope-vaccines which were assumed to work for all alleles. In total, there were 297 unique epi predicted from the 3 proteins and amongst, S regions had the highest number of epi (n = 186). Epitope-densities (Depi) between genotypes A and D were similar. A number of mutations that hindered HLA-peptide binding were observed. We also identified antigenic and genotype-specific peptides with characteristics that are well suited for the development of sensitive diagnostic kits. This study identified candidate peptides that can be used for developing multi-epitope vaccines and highly sensitive diagnostic kits against HBV infection in an African population. Our results suggest that viral variability may hinder HBV peptide-MHC binding, required to initiate a cascade of immunological responses against infection. [ABSTRACT FROM AUTHOR]