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Unprecedented and dramatic transformations are occurring in the Arctic in response to climate change, but academic, public, and political discourse has disproportionately focussed on the most visible and direct aspects of change, including sea ice melt, permafrost thaw, the fate of charismatic megafauna, and the expansion of fisheries. Such narratives disregard the importance of less visible and indirect processes and, in particular, miss the substantive contribution of the shelf seafloor in regulating nutrients and sequestering carbon. Here, we summarise the biogeochemical functioning of the Arctic shelf seafloor before considering how climate change and regional adjustments to human activities may alter its biogeochemical and ecological dynamics, including ecosystem function, carbon burial, or nutrient recycling. We highlight the importance of the Arctic benthic system in mitigating climatic and anthropogenic change and, with a focus on the Barents Sea, offer some observations and our perspectives on future management and policy.

Ecosystems and their biota operate on cyclic rhythms, often entrained by predictable, small-scale changes in their natural environment. Recording and understanding these rhythms can detangle the effect of human induced shifts in the climate state from natural fluctuations. In this study, we assess long-term patterns of reproductive investment in the Antarctic sea urchin, Sterechinus neumayeri, in relation to changes in the environment to identify drivers of reproductive processes. Polar marine biota are sensitive to small changes in their environment and so serve as a barometer whose responses likely mirror effects that will be seen on a wider global scale in future climate change scenarios. Our results indicate that seasonal reproductive periodicity in the urchin is underpinned by a multiyear trend in reproductive investment beyond and in addition to, the previously reported 18–24 month gametogenic cycle. Our model provides evidence that annual reproductive investment could be regulated by an endogenous rhythm since environmental factors only accounted for a small proportion of the residual variation in gonad index. This research highlights a need for multiyear datasets and the combination of biological time series data with large-scale climate metrics that encapsulate multi-factorial climate state shifts, rather than using single explanatory variables to inform changes in biological processes.

This study reports the first multi-year observations on the reproductive patterns for an Antarctic predator/scavenger, Odontaster validus (Koehler 1912). Seastars were collected monthly from a shallow site (15–20 m depth) near the British Antarctic Survey (BAS) Rothera Research Station (Adelaide Island, 67°34′S 68°08′W) from July 1997 to January 2001. Reproductive condition, oocyte size frequencies and spermatogenesis were examined in at least ten seastars each month using histological and image analysis techniques. Gonad indices (GI) and pyloric caeca indices (PI) were also examined in the same samples. Female and male GIs varied seasonally, in parallel with a reduction in the proportion of large oocytes and mature sperm in the gonad in August to mid-October following winter spawning. Despite there being remarkable consistency in the timing of spawning from year to year, differences in the reproductive condition of individuals were apparent. Patterns in the digestive tissues also varied with season, peaking in December and reaching a minimum in February in two of the three study years. This weaker annual pattern may partly reflect the varied diet of this predator/scavenger species, which is not directly dependant on the timing and magnitude of the annual phytoplankton bloom. Pooled oocyte size distributions and residual analysis suggested that oogenesis progressed over 18–24 months, with the largest of the two size classes (maximum diameter = 183 μm) being spawned annually. This pattern of oocyte growth and spawning was previously reported in the early 1960s for an O. validus population from McMurdo Sound, which lies south of Rothera by 10° latitude. The extremely catholic diet of this predator/scavenger suggests the reproductive patterns of the seastar will be less susceptible to changes in food supply compared to polar suspension feeders or deposit feeders.

Fludarabine (FDR) therapy gives a response rate of about 30% in previously treated patients with Waldenström's macroglobulinemia (WM). The combination of FDR and cyclophosphamide (Cy) has been shown to be effective in chronic lymphoproliferative disorders. We administered the combination of FDR (30 mg/m2 i.v. D1-D3) and Cy (300 mg/m2 i.v. D1-D3) to 49 patients. Median age was 64 years. The median hemoglobin, albumin, beta 2 microglobulin and immunoglobulin M (IgM) levels were 9.9 g/100 ml, 39.6 g/l, 3 mg/l and 24.7 g/l, respectively. In all, 14 patients (29%) had not previously been treated. FDR/Cy was administered every 4 weeks for a median of four cycles. In all, 38 patients (77.6%) had partial responses, nine had stable disease and two had progressive disease. After a median of follow-up of 25 months, six patients relapsed and two patients developed large-cell lymphoma. The median time to treatment failure was 27 months. The main toxicity was hematological. In all, 12 patients died, four from progression, one from large-cell lymphoma, three from infection and four from a second malignancy. Two factors negatively influenced overall and event-free survival, age65 years and IgM40 g/l. The FDR/Cy combination, therefore, gives a high response rate in WM, even in previously treated patients with factors of poor prognosis.

The present study examined the predictive power of Big Five personality dimensions, a situational measure of service orientation and a reading comprehension measure as predictors of Flight Attendant training criteria. The criteria consisted of multiple ratings made by trainers of trainees across a number of training dimensions. At least partial data was collected on 424 Flight Attendant trainees. Results indicated significant correlations between all three predictors and a number of the training criteria.

Due to an unfortunate error, the original version of this article has been published with an error in the reference citation. It should be Brockington et al. (2007) instead of Brockington et al. (2006).