On the origins of islands

Theoretical and Experimental Linguistic

Properties of Sarychev sulphate aerosols over the Arctic

Aerosols from the Sarychev Peak volcano entered the Arctic region less than a week after the strongest SO2 eruption on June 15 and 16, 2009 and had, by the second week in July, spread out over the entire Arctic region. These predominantly stratospheric aerosols were determined to be sub-micron in size and inferred to be composed of sulphates produced from the condensation of SO2 gases emitted during the eruption. Average (500 nm) Sarychev-induced stratospheric optical depths over the Polar Environmental Atmospheric Research Laboratory (PEARL) at Eureka, Nunavut, Canada were found to be between 0.03 and 0.05 during the months of July and August, 2009. This estimate, derived from sunphotometry and integrated lidar backscatter profiles was consistent with averages derived from lidar estimates over Ny-Ålesund (Spitsbergen). The Sarychev SOD e-folding time at Eureka, deduced from lidar profiles, was found to be approximately 4 months relative to a regression start date of July 27. These profiles initially revealed the presence of multiple Sarychev plumes between the tropopause and about 17 km altitude. After about two months, the complex vertical plume structures had collapsed into fewer, more homogeneous plumes located near the tropopause. It was found that the noisy character of daytime backscatter returns induced an artifactual minimum in the temporal, pan-Arctic, CALIOP SOD response to Sarychev sulphates. A depolarization ratio discrimination criterion was used to separate the CALIOP stratospheric layer class into a low depolarization subclass which was more representative of Sarychev sulphates. Post-SAT (post Sarychev Arrival Time) retrievals of the fine mode effective radius (reff,f) and the logarithmic standard deviation for two Eureka sites and Thule, Greenland were all close to 0.25 μm and 1.6 respectively. The stratospheric analogue to the columnar reff,f average was estimated to be reff,f(+) = 0.29 μm for Eureka data. Stratospheric, Raman lidar retrievals at Ny-Ålesund, yielded a post-SAT average of reff,f(+) = 0.27 μm. These results are ~ 50% larger than the background stratospheric-aerosol value. They are also about a factor of two larger than modeling values used in recent publications or about a factor of five larger in terms of (per particle) backscatter cross section

Evidence for a Decline in Northern Quebec (Nunavik) Belugas

belugas were present at the surface in the offshore areas of James Bay and Hudson Bay, respectively. An additional 39 animals were observed in estuaries during the coastal survey, resulting in an index estimate of 1194 (SE = 507) in eastern Hudson Bay. No belugas were observed in Ungava Bay. Observations from systematic surveys conducted in 1993 and 2001 were analyzed using both line-transect and strip-transect methods to allow comparisons with the strip-transect survey conducted in 1985. A population model incorporating harvest information and fitted to the aerial survey data indicates that the number of belugas in eastern Hudson Bay has declined by almost half because of high harvest levels. Subsistence harvest levels must be reduced significantly if this population is to recover. Key words: beluga, aerial survey, Nunavik, harvesting, northern Quebec, abundance RÉSUMÉ. Des relevés aériens systématiques de bélugas (Delphinapterus leucas) par échantillonnage en ligne ont été effectué

Infliximab Reduces Endoscopic, but Not Clinical, Recurrence of Crohn's Disease After Ileocolonic Resection.

BACKGROUND & AIMS: Most patients with Crohn's disease (CD) eventually require an intestinal resection. However, CD frequently recurs after resection. We performed a randomized trial to compare the ability of infliximab vs placebo to prevent CD recurrence. METHODS: We evaluated the efficacy of infliximab in preventing postoperative recurrence of CD in 297 patients at 104 sites worldwide from November 2010 through May 2012. All study patients had undergone ileocolonic resection within 45 days before randomization. Patients were randomly assigned (1:1) to groups given infliximab (5 mg/kg) or placebo every 8 weeks for 200 weeks. The primary end point was clinical recurrence, defined as a composite outcome consisting of a CD Activity Index score >200 and a >/=70-point increase from baseline, and endoscopic recurrence (Rutgeerts score >/=i2, determined by a central reader) or development of a new or re-draining fistula or abscess, before or at week 76. Endoscopic recurrence was a major secondary end point. RESULTS: A smaller proportion of patients in the infliximab group had a clinical recurrence before or at week 76 compared with the placebo group, but this difference was not statistically significant (12.9% vs 20.0%; absolute risk reduction [ARR] with infliximab, 7.1%; 95% confidence interval: -1.3% to 15.5%; P = .097). A significantly smaller proportion of patients in the infliximab group had endoscopic recurrence compared with the placebo group (30.6% vs 60.0%; ARR with infliximab, 29.4%; 95% confidence interval: 18.6% to 40.2%; P /=i2 (22.4% vs 51.3%; ARR with infliximab, 28.9%; 95% confidence interval: 18.4% to 39.4%; P < .001). Patients previously treated with anti-tumor necrosis factor agents or those with more than 1 resection were at greater risk for clinical recurrence. The safety profile of infliximab was similar to that from previous reports. CONCLUSIONS: Infliximab is not superior to placebo in preventing clinical recurrence after CD-related resection. However, infliximab does reduce endoscopic recurrence. ClinicalTrials.gov ID NCT01190839