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The Government of Canada has committed to protect 10% of its coastal and marine areas. One means of protection is through the development of Marine Protected Areas (MPAs). In Nunavut, Regional Inuit Associations along with other stakeholders provided guidance to identify potential Areas of Interest (AOI) for a Marine Protected Area process. In the Kivalliq Region of Nunavut, the marine waters adjacent to Southampton Island (SI) were identified as one AOI. The Southampton Island Ecologically and Biologically Significant Area (SI EBSA) provides valuable migratory habitat for Beluga (Delphinapterus leucas), Bowhead (Balaena mysticetus) and Narwhal (Monodon monoceros), as well as feeding and calving areas for a proportion of these marine mammal populations. The SI EBSA is home to large aggregations of seabirds such as the two colonies of Thick-Billed Murres (Uria lomvia) on Coats Island and the largest single colony of Common Eiders (Somateria mollissima) in Nunavut. Resident marine mammals to the SI EBSA include Walrus (Odobenus rosmarus) and Polar Bear (Ursus maritimus) populations. In addition, migratory Arctic Char (Salvelinus alpinus) are the most abundant salmonid that is available for subsistence harvesting to Inuit communities living adjacent to the SI EBSA. The recurring polynya in Roes Welcome Sound provides approximately 52 km2 of open water during winter and is believed to play an important role in deep water formation and nutrient cycling in Hudson Bay, which may support high benthic productivity, and in turn large numbers of migrating birds and marine mammals. The polynya also provides valuable overwintering habitat for Walruses, Bearded Seals (Erignathus barbatus), and small numbers of Belugas in some years. This document provides a summary and synthesis of existing information relevant to the SI EBSA which has been used to determine its ecological significance, as well as known knowledge gaps and vulnerabilities. [ABSTRACT FROM AUTHOR]

Citing the capacity of anadromous sturgeon species to undertake lengthy spawning migrations, Auer (1996) hypothesized that a minimum of 250–300 km of barrier-free lake and river habitat might be required to support self-sustaining populations of Lake SturgeonAcipenser fulvescens. Twenty years later, the biological understanding of this potamodromous species has improved considerably, but there has been minimal effort to reconcile the barrier-free hypothesis with the persistence of Lake Sturgeon populations in impounded habitats and improve the understanding of what constitutes a functional population-level habitat unit for this species of conservation concern. Herein, POPAN mark–recapture models and sequential length-frequency histograms were used to examine contemporary Lake Sturgeon abundance and population trajectories in three small reaches (230, 50, and 10 river kilometers [rkm]) of the Nelson and Winnipeg rivers (Manitoba), developed for hydroelectric power generation. Approximately two decades after harvest closures, results indicate that population recovery is occurring in all three reaches examined. Mechanisms other than in situ reproduction or recruitment (i.e., stocking and immigration) for increasing abundance are confidently discounted. Based on these results and other observations of contemporary persistence of Lake Sturgeon populations in impounded environments as well as recent genetic observations indicative of historical population structuring along the flow axes of naturally fragmented Boreal Shield rivers, it is contended that the barrier-free hypothesis should no longer be cited as a “rule of thumb” with regard to the habitat quantity required to support self-sustaining Lake Sturgeon populations. Rather, the concept of an uninterrupted “spawn–drift–settle–establish” habitat sequence as the cornerstone of a functional population-level habitat unit may have broader relevance to species recovery initiatives and management. Given appropriate geomorphologic and hydraulic conditions, Lake Sturgeon populations can thrive—and in Boreal Shield rivers likely have for thousands of years—in lake, river, or impoundment sections as small as 10 rkm. Received March 27, 2017; accepted July 3, 2017 Published online September 18, 2017 [ABSTRACT FROM AUTHOR]

Success of lake sturgeon ( Acipenser fulvescens Rafinesque, 1817) stocking programmes has rarely been evaluated. As of the early 1990s, Lake Sturgeon populations were nearly extirpated from several sections of the upper Nelson River, Manitoba, at least in part due to historical overexploitation. Between 1994 and 2011, 20 885 fingerlings (age-0, untagged) and 1117 yearlings (age-1, 1014 PIT tagged) were stocked into an upper Nelson River reach. In fall 2012, a Lake Sturgeon population inventory using gill nets assessed post-release survival/retention of stocked fish. Of 91 unique Lake Sturgeon captured, 67 (74%) possessed PIT tags, signifying they were stocked at age-1. Relative recruitment success was conservatively estimated to be 17.7 times greater for age-1 vs age-0 stocked fish based only on PIT tag recapture data. However, including 19 additional fish identified as stocked at age-1 based on atypical 'first' annuli patterns, the revised relative recruitment success rate was 130 times greater for age-1 vs age-0. An interpreted consensus ageing method produced correct age assignment 97% of the time for juveniles of known age, despite complications caused by overwinter growth in the hatchery. [ABSTRACT FROM AUTHOR]

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst)  eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140  MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

This corrects the article DOI: 10.1103/PhysRevLett.121.051301.

We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 g CDMS high-voltage device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1  MeV/c^{2}. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 g d). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.

We report the result of a blinded search for weakly interacting massive particles (WIMPs) using the majority of the SuperCDMS Soudan data set. With an exposure of 1690 kg d, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP-nucleon cross section of 1.4×10^{-44} (1.0×10^{-44})  cm^{2} at 46  GeV/c^{2}. These results set the strongest limits for WIMP-germanium-nucleus interactions for masses >12  GeV/c^{2}.

Cancer registries help to establish and maintain cancer incidence reporting systems, serve as a resource for investigation of cancer and its causes, and provide information for planning and evaluation of preventive and control programs. However, their wider role in directly enhancing oncology drug access has not been fully explored. We examined the value of cancer registries in oncology drug access in the Asia-Pacific region on three levels: (1) specific registry variable types; (2) macroscopic strategies on the national level; and (3) a regional cancer registry network. Using literature search and proceedings from an expert forum, this paper covers recent cancer registry developments in eight economies in the Asia-Pacific region - Australia, China, Hong Kong, Malaysia, Singapore, South Korea, Taiwan, and Thailand - and the ways they can contribute to oncology drug access. Specific registry variables relating to demographics, tumor characteristics, initial treatment plans, prognostic markers, risk factors, and mortality help to anticipate drug needs, identify high-priority research area and design access programs. On a national level, linking registry data with clinical, drug safety, financial, or drug utilization databases allows analyses of associations between utilization and outcomes. Concurrent efforts should also be channeled into developing and implementing data integrity and stewardship policies, and providing clear avenues to make data available. Less mature registry systems can employ modeling techniques and ad-hoc surveys while increasing coverage. Beyond local settings, a cancer registry network for the Asia-Pacific region would offer cross-learning and research opportunities that can exert leverage through the experiences and capabilities of a highly diverse region.

We compared total and cause-specific mortality for workers at the Pantex nuclear weapons assembly facility employed between 1951 and 31 December 1978 with expected mortality based on U.S. death rates. We observed significantly fewer deaths than expected from all causes of death, all cancers, digestive cancers, lung cancer, arteriosclerotic heart disease, and digestive diseases. There were no causes of death which occurred significantly more frequently than expected. Analyses of worker mortality by duration of employment, time since first employment, and radiation exposure greater than 1.00 rem produced similar results. We found no evidence that mortality from any cause of death was increased as a result of employment at Pantex.