Remote Sensing of Permafrost by Ground-Penetrating Radar at Two Airports in Arctic Canada

Over a cycle of seasons, ground-penetrating radar studies were carried out at Inuvik and Rankin Inlet, Northwest Territories. The two airports are part of the Forward Operating Location (FOL) program of the Department of National Defence and have been slated for significant upgrading of runways, taxiways and parking aprons. This provided a good opportunity to investigate the extent of permafrost and its seasonal variation at two locations distributed over a wide geographic area. The study method involved specific and repeated traverses with a Pulse EKKO III ground-penetrating radar unit. The survey was successful in locating massive ice bodies, imaging several existing problem areas beneath runways and mapping the seasonal depth of thaw in permafrost. The study results imply that future monitoring at FOL sites should be continued in light of suggested ground stability problems due to global warming.Key words: Canadian Arctic, ground-penetrating radar, permafrost, global warming,  airport, Forward Operating LocationMot clés: Arctic canadien,  géoradar, pergélisol, réchauffement atmosphéric, aéroport, Emplacemen Avancés d’opération

Linking Distributive and Procedural Justice to Employee Engagement Through Social Exchange: A Field Study in India

Research linking justice perceptions to employee outcomes has referred to social exchange as its central theoretical premise. We tested a conceptual model linking distributive and procedural justice to employee engagement through social exchange mediators, namely, perceived organizational support and psychological contract, among 238 managers and executives from manufacturing and service sector firms in India. Findings suggest that perceived organizational support mediated the relationship between distributive justice and employee engagement, and both perceived organizational support and psychological contract mediated the relationship between procedural justice and employee engagement. Theoretical and practical implications with respect to organizational functions are discussed

Preservation of viral genomes in 700-y-old caribou feces from a subarctic ice patch

Viruses preserved in ancient materials provide snapshots of past viral diversity and a means to trace viral evolution through time. Here, we use a metagenomics approach to identify filterable and nuclease-resistant nucleic acids preserved in 700-y-old caribou feces frozen in a permanent ice patch. We were able to recover and characterize two viruses in replicated experiments performed in two different laboratories: a small circular DNA viral genome (ancient caribou feces associated virus, or aCFV) and a partial RNA viral genome (Ancient Northwest Territories cripavirus, or aNCV). Phylogenetic analysis identifies aCFV as distantly related to the plant-infecting geminiviruses and the fungi-infecting Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 and aNCV as within the insect-infecting Cripavirus genus. We hypothesize that these viruses originate from plant material ingested by caribou or from flying insects and that their preservation can be attributed to protection within viral capsids maintained at cold temperatures. To investigate the tropism of aCFV, we used the geminiviral reverse genetic system and introduced a multimeric clone into the laboratory model plant Nicotiana benthamiana. Evidence for infectivity came from the detection of viral DNA in newly emerged leaves and the precise excision of the viral genome from the multimeric clones in inoculated leaves. Our findings indicate that viral genomes may in some circumstances be protected from degradation for centuries

Mutations in the sarcomere protein gene MYH7 in Ebstein's anomaly

BACKGROUND: Ebstein's anomaly is a rare congenital heart malformation characterized by adherence of the septal and posterior leaflets of the tricuspid valve to the underlying myocardium. An association between Ebstein's anomaly with left ventricular noncompaction (LVNC) and mutations in MYH7 encoding beta-myosin heavy chain has been reported; here we have screened for MYH7 mutations in a cohort of probands with Ebstein's anomaly in a large population-based study. METHODS AND RESULTS: Mutational analysis in a cohort of 141 unrelated probands with Ebstein's anomaly was performed by next generation sequencing and direct DNA sequencing of MYH7. Heterozygous mutations were identified in 8 of 141 samples (6%). Seven distinct mutations were found, 5 were novel and 2 were known to cause hypertrophic cardiomyopathy (HCM). All mutations except for one 3-bp deletion were missense mutations, one was a de novo change. Mutation-positive probands and family members showed various congenital heart malformations as well as LVNC. Among 8 mutation-positive probands, 6 had LVNC, whereas among 133 mutation-negative probands, none had LVNC. The frequency of MYH7 mutations was significantly different between probands with and without LVNC accompanying Ebstein's anomaly (p<0.0001). LVNC segregated with the MYH7 mutation in the pedigrees of three of the probands, one of which also included another individual with Ebstein's anomaly. CONCLUSIONS: Ebstein's anomaly is a congenital heart malformation that is associated with mutations in MYH7. MYH7 mutations are predominantly found in Ebstein's anomaly associated with LVNC and may warrant genetic testing and family evaluation in this subset of patients