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We describe and model the evolution of a recent landslide, tsunami, outburst flood, and sediment plume in the southern Coast Mountains, British Columbia, Canada. On November 28, 2020, about 18 million m3 of rock descended 1,000 m from a steep valley wall and traveled across the toe of a glacier before entering a 0.6 km2 glacier lake and producing >100‐m high run‐up. Water overtopped the lake outlet and scoured a 10‐km long channel before depositing debris on a 2‐km2 fan below the lake outlet. Floodwater, organic debris, and fine sediment entered a fjord where it produced a 60+km long sediment plume and altered turbidity, water temperature, and water chemistry for weeks. The outburst flood destroyed forest and salmon spawning habitat. Physically based models of the landslide, tsunami, and flood provide real‐time simulations of the event and can improve understanding of similar hazard cascades and the risk they pose. Plain Language Summary: Glacier retreat exposes unstable slopes that can suddenly fail. We describe and model one such event with far‐reaching consequences. The landslide mass (50 million tonnes, equivalent to the combined mass of all Canadian automobiles) entered and suddenly drained a 0.6‐km2 alpine lake in the southern Coast Mountains of British Columbia. Displaced water destroyed salmon‐spawning habitat over a distance of 8.5 km and created a plume of sediment and organic matter more than 60 km from the head of the fjord into which the floodwaters discharged. Physically based models are able to simulate the hazard cascade, and such models could be used to improve hazard and risk assessments of these events under future climate change. Key Points: Rapid glacier retreat created conditions that allowed a geohazard cascade to occur in a steep mountain valleyWe describe and model a recent landslide, tsunami, and outburst flood that typifies a deglacial geohazard cascadeFuture work should predict new glacial lakes and use physically based models to simulate the slope, tsunami, and outburst flood hazards [ABSTRACT FROM AUTHOR]

Studies suggest that patients carrying a BRCA variant of uncertain significance ( VUS) may have lingering confusion concerning results interpretation. Counseling for uninformative BRCA-negative ( UN) results is thought to be more straightforward, despite the fact that both results lead to similar methods of empiric cancer risk counseling. This study compared surgical choices and perceptions between 71 patients with VUS results and 714 patients with UN results. All patients underwent genetic counseling because of a personal or family history of breast or ovarian cancer between 1997 and 2010, and completed a 2-year follow-up survey. Risk-reducing mastectomy rates in both groups were 7% (p = 1.00) and risk-reducing oophorectomy rates were 5% and 3%, respectively (p = 0.42). The VUS group reported less cancer distress reduction than the UN group (23.0% vs 35.8%, respectively, p = 0.043). Over 90% of both groups found the counseling process helpful. Overall, the study suggests that VUS results disclosed in genetic counseling did not cause excessive surgery or exaggerated cancer distress, though patients with a VUS found counseling somewhat less informative or reassuring. Future research on communication of VUS results, including pre-and post-test counseling, is essential for full realization of the potential for genomic medicine. [ABSTRACT FROM AUTHOR]

Brady Glacier is a large Alaskan tidewater glacier that is beginning a period of substantial retreat. Examination of 27 Landsat and MODIS images from the period 2003 to 2011 indicates that Brady Glacier has a mean equilibrium line altitude (ELA) of 745 m and accumulation area ratio (AAR) of 0.40. The zero balance ELA is 600 m and equilibrium AAR 0.65. The negative mass balance associated with the increased ELA has triggered thinning of 20-100 m over most of the glacier below the ELA from 1948 to 2010. The thinning has caused substantial retreat of seven calving distributary termini of the glacier. Thinning and retreat have led to an increase in the width of and water depth at the calving fronts. In contrast, the main terminus has undergone only minor retreat since 1948. In 2010, several small proglacial lakes were evident at the terminus. By 2000, a permanent outlet river issuing from Trick Lake had developed along the western glacier margin. Initial lake development at the terminus combined with continued mass losses will lead to expansion of the lakes at the main terminus and retreat by calving. The glacier bed is likely below sea level along the main axis of Brady Glacier to the glacier divide. Retreat of the main terminus in the lake will likely lead to a rapid calving retreat similar to Bear, Excelsior, Norris, Portage and Yakutat glaciers. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The denitrification capacity of wetlands, riparian zones, and aquifers in glacial outwash areas is well documented, but little or no information exists for volcanic profiles, particularly those containing relict organic matter contained in or on top of paleosols (old soils buried by volcanic deposits) below the groundwater table. Relict carbon contained in these layers could provide the necessary electrons to fuel heterotrophic denitrification. To the best of our knowledge, this is the first study investigating the denitrification capacity in both the unsaturated and saturated zone of volcanic profiles. Samples from three profile types with differing organic matter distribution were amended with 15N‐enriched nitrate (NO3−) and incubated in the laboratory under anaerobic conditions. Dinitrogen (N2) dominated the 15N gas fluxes; averaged across all samples, it accounted for 96% of the total 15N (nitrous oxide [15N2O] and 15N2) gas fluxes. Dinitrogen fluxes were generally highest in the A horizon samples (4.1–6.2 nmol N g−1 h−1), but substantial fluxes were also observed in some paleosol layers (up to 0.72 nmol N g−1 h−1). A significant correlation (p < 0.001) was found between the concentration of extractable dissolved organic carbon and the total 15N gas flux produced in samples from below the A horizon, suggesting that heterotrophic denitrification was the dominant NO3− attenuation process in this study. Extrapolation of lab‐derived denitrification capacities to field conditions suggests that the denitrification capacity of profiles containing relict soil organic matter in the saturated zone exceeds the estimated N leaching from the root zone. [ABSTRACT FROM AUTHOR]

In this technical note we present the design, installation, and evaluation of a field monitoring system to directly measure water fluxes through a vadose zone. The system is based on use of relatively new measurement technology-automated equilibrium tension lysimeters (AETLs). An AETL uses a porous sintered stainless-steel plate to provide a comparatively large sampling area (0.20 m2) with a continuously controlled vacuum applied under the plate. This vacuum is in "equilibrium" with the surrounding vadose zone tension to ensure measured fluxes represent those under undisturbed conditions. Fifteen of these AETLs have been installed at five depths through a layered volcanic vadose zone to study the impact of land use changes on water quality in Lake Taupo, New Zealand. We describe the development and testing of the AETLs, the methods used for installing these devices, a condensed data set of the measured physical properties of the vadose zone, and the initial results from the in situ operation of the AETLs, including the preliminary results from a bromide tracer test. For an AETL installed at the 0.4-m depth, where soil pressure heads are most dynamic, the average deviation between the target reference pressure head, as measured in the undisturbed vadose zone and the pressure head measured above the sampling plate was only 5.4 hPa over a 180-d period. The bromide recovered in an AETL at the same depth was equivalent to 96% of the bromide pulse applied onto the surface area directly above the AETL. We conclude that this measurement technique provides an accurate and robust method of measuring vadose zone fluxes. These measurements can ultimately contribute to better understanding of the water transport and contaminant transformation processes through vadose zones. [ABSTRACT FROM AUTHOR]

The kinetics and nature of the nondialyzable cytotoxic activity which appeared in the serum after the consumption of 1.2 g ethyl alcohol per kilogram body weight over 45 min was studied in six healthy volunteers and eight patients with histologically proven alcohol-related cirrhosis of the liver. Whereas the cytotoxic activity in the dialyzed serum showed a single peak with a maximum value 8 hr after the start of ethanol consumption in the healthy volunteers, it showed two peaks with maximum values at 2 and 8 hr in the patients with cirrhosis. Studies of the fractions obtained by Sephacryl-S-300 gel filtration of the 2-hr postalcohol serum samples revealed substantial cytotoxic activity in the fractions containing both the albumin peak and the IgG peak in the patients with cirrhosis and only in the fractions containing the albumin peak in the healthy volunteers. Experiments with pure IgG preparations obtained from prealcohol and 2-hr postalcohol sera by chromatography on Q-Sepharose Fast Flow anion-exchange resin showed considerable cytotoxic activity in the preparations from the patients with cirrhosis and little or no cytotoxic activity in those from the healthy volunteers. Thus, the early peak of the biphasic serum cytotoxicity curve seen after ethanol consumption by patients with cirrhosis appeared to be caused by the development of a substantial cytotoxic activity in the IgG molecules during the first 2 hr. When prealcohol sera from healthy subjects and patients with cirrhosis were incubated with various concentrations of [14C]acetaldehyde at 37°C for 6 hr, and the reacted sera were dialyzed and subjected to gel filtration, the proportion of radioactivity associated with the IgG peak was found to increase progressively with increasing concentrations of [14C]acetaldehyde. It therefore appeared that the differences in the nature and kinetics of the cytotoxic proteins which circulate after ethanol consumption in healthy subjects and patients with cirrhosis may be due to the generation of higher levels of blood acetaldehyde in the latter. The differences may also be partly related to the increased serum IgG levels and the reduced serum albumin levels often seen in alcohol-induced cirrhosis. [ABSTRACT FROM AUTHOR]

1. The effects of salmeterol hydroxynaphthoate (50 micrograms, 8.3 x 10(-8) M) and salbutamol (200 micrograms, 3.5 x 10(-7) M) on sGaw were compared in a double-blind, placebo-controlled, randomised study in 10 normal subjects. 2. SGaw increased by 29% (14-43) (mean (CI)), 5 min after salmeterol and by 35% (19-51) at 15 min compared with an increase of 32% (14-51) and 37% (10-63) after salbutamol and 4% (-3-11) and 8% (0-16) after placebo. 3. The mean area under the sGaw-time curve (AUC480) after salmeterol inhalation was 22,500 kPa-1 (10,100-39,500) compared with 14100 kPa-1 (8020-24,500) after salbutamol and 5300 kPa-1 (1500-10,400) after placebo. 4. Salmeterol produced a significantly prolonged bronchodilator effect compared with salbutamol in normals. [ABSTRACT FROM AUTHOR]