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OBJECTIVES: The aim of this study was to: 1) provide tissue validation of quantitative T2 mapping to measure plaque lipid content; and 2) investigate whether this technique could discern differences in plaque characteristics between symptom-related and non–symptom-related carotid plaques. BACKGROUND: Noninvasive plaque lipid quantification is appealing both for stratification in treatment selection and as a possible predictor of future plaque rupture. However, current cardiovascular magnetic resonance (CMR) methods are insensitive, require a coalesced mass of lipid core, and rely on multicontrast acquisition with contrast media and extensive post-processing. METHODS: Patients scheduled for carotid endarterectomy were recruited for 3-T carotid CMR before surgery. Lipid area was derived from segmented T2 maps and compared directly to plaque lipid defined by histology. RESULTS: Lipid area (%) on T2 mapping and histology showed excellent correlation, both by individual slices (R = 0.85, p < 0.001) and plaque average (R = 0.83, p < 0.001). Lipid area (%) on T2 maps was significantly higher in symptomatic compared with asymptomatic plaques (31.5 +/- 3.7% vs. 15.8 +/- 3.1%; p = 0.005) despite similar degrees of carotid stenosis and only modest difference in plaque volume (128.0 +/- 6.0 mm3 symptomatic vs. 105.6 +/- 9.4 mm3 asymptomatic; p = 0.04). Receiver-operating characteristic analysis showed that T2 mapping has a good ability to discriminate between symptomatic and asymptomatic plaques with 67% sensitivity and 91% specificity (area under the curve: 0.79; p = 0.012). CONCLUSIONS: CMR T2 mapping distinguishes different plaque components and accurately quantifies plaque lipid content noninvasively. Compared with asymptomatic plaques, greater lipid content was found in symptomatic plaques despite similar degree of luminal stenosis and only modest difference in plaque volumes. This new technique may find a role in determining optimum treatment (e.g., providing an indication for intensive lipid lowering or by informing decisions of stents vs. surgery).

This paper is a revised version of WG-EMM-15/28, which uses a question and answer format to explain the management of the Antarctic krill (Euphausia superba) fishery in the subareas 48.1 to 48.4, and current knowledge about the state of the regional krill stock. The revisions provide a new, precautionary assessment of exploitation rate in this fishery. The effective regional catch limit (or “trigger level”), established in 1991, is 0.62 million tonnes year-1 , equivalent to ~1% of the regional biomass estimated in 2000. Additional subarea catch limits were established in 2009. There is some evidence for a decline in the abundance of krill in the 1980s, but no evidence of further decline over more recent decades. Biomass indices from local monitoring programmes established in the 1990s and 2000s also show no evidence of a further decline. Extrapolation from these local monitoring programmes provides conservative estimates of the regional biomass in recent years. This suggests that the trigger level would be equivalent to a long-term exploitation rate (catch divided by biomass) of

Objectives The aim of this study was to: 1) provide tissue validation of quantitative T2 mapping to measure plaque lipid content; and 2) investigate whether this technique could discern differences in plaque characteristics between symptom-related and non–symptom-related carotid plaques. Background Noninvasive plaque lipid quantification is appealing both for stratification in treatment selection and as a possible predictor of future plaque rupture. However, current cardiovascular magnetic resonance (CMR) methods are insensitive, require a coalesced mass of lipid core, and rely on multicontrast acquisition with contrast media and extensive post-processing. Methods Patients scheduled for carotid endarterectomy were recruited for 3-T carotid CMR before surgery. Lipid area was derived from segmented T2 maps and compared directly to plaque lipid defined by histology. Results Lipid area (%) on T2 mapping and histology showed excellent correlation, both by individual slices (R = 0.85, p < 0.001) and plaque average (R = 0.83, p < 0.001). Lipid area (%) on T2 maps was significantly higher in symptomatic compared with asymptomatic plaques (31.5 ± 3.7% vs. 15.8 ± 3.1%; p = 0.005) despite similar degrees of carotid stenosis and only modest difference in plaque volume (128.0 ± 6.0 mm3 symptomatic vs. 105.6 ± 9.4 mm3 asymptomatic; p = 0.04). Receiver-operating characteristic analysis showed that T2 mapping has a good ability to discriminate between symptomatic and asymptomatic plaques with 67% sensitivity and 91% specificity (area under the curve: 0.79; p = 0.012). Conclusions CMR T2 mapping distinguishes different plaque components and accurately quantifies plaque lipid content noninvasively. Compared with asymptomatic plaques, greater lipid content was found in symptomatic plaques despite similar degree of luminal stenosis and only modest difference in plaque volumes. This new technique may find a role in determining optimum treatment (e.g., providing an indication for intensive lipid lowering or by informing decisions of stents vs. surgery)., Graphical abstract

We present a novel index of Antarctic krill biomass in CCAMLR subareas 48.1 to 48.4, based on data from scientific nets and covering the years between 2000 and 2011. The annual biomass variation was significant (CV=73%) but no systematic change in krill biomass was evident during the period. The index also suggests that realised exploitation rates were below 0.5% (i.e. catch was

The performance of uncertainty estimation procedures was evaluated with respect to accuracy. A confidence statement is said to be accurate if the confidence point achieves the desired probability coverage. A Monte Carlo experiment with 100 trials was conducted with a true population that experienced contrast between low and high fishing mortality. Observations for the last 25 years were drawn stochastically by adding measurement error. The assessment approaches were VPA-based (ADAPT and XSA with errors on the effort data). The Delta Method , parametric bootstrap and non-parametric bootstrap (NPB), and a Bayesian approach were used to quantify coverage and assess the accuracy of confidence limits of estimated interest parameters (F0.1, SSB and TACF0.1 in year 26) by comparing against the true values. Variations of the Delta Method and bootstrap were used to account for statistical estimation bias. The results indicated that accurate inference statements are possible with the different approaches and that bias correction can improve accuracy when it can be applied. The bias-corrected Delta-ADAPT and bias-corrected NPB-ADAPT applications performed best. Inference statements about F0.1 were more accurate than those for SSB or TAC.

We report on a test of three methods that have been used by ICES in making probability statements about fisheries forecasts to management agencies (XSA/WGMTERM, ICA/ICP, and a stochastic projection method that was first applied to North Sea herring). The principle of the test is to calculate many stock assessments and forecasts using historic data, and to compare probability statements about some quantities (forecast biomass, relative biomass, catch etc.) with the latest and presumably more reliable estimates. For most ICES and NAFO stocks where a sufficiently long time-series exists, we calculate retrospective (8 year before present) assessments and then calculate medium term forecasts 5 years forwards. By comparing the frequencies of expected and actual outcomes, we conclude that some methods can be used to make reasonably reliable probability statements about relative biomass (e.g. biomass relative to biomass at some time in the past), but that for most other quantities and most methods the accuracy of probability estimates is very poor. In general, the methods tended to underestimate uncertainty and there was a relatively large proportion of "unexpected" outcomes in the forecasts.