To develop evidence-based recommendations for the use of imaging modalities in primary large vessel vasculitis (LVV) including giant cell arteritis (GCA) and Takayasu arteritis (TAK).European League Against Rheumatism (EULAR) standardised operating procedures were followed. A systematic literature review was conducted to retrieve data on the role of imaging modalities including ultrasound, MRI, CT and [ 18

Neuroimaging biomarkers, namely hippocampal volume loss, temporoparietal hypometabolism, and neocortical ␤-amyloid (A␤) deposition, are included in the recent research criteria for preclinical Alzheimer's disease (AD). However, how to use these biomarkers is still being debated, especially regarding their sequence. Our aim was to characterize the cognitive and brain profiles of elders classified as positive or negative for each biomarker to further our understanding of their use in the preclinical diagnosis of AD. Fifty-four cognitively normal individuals (age ϭ 65.8 Ϯ 8.3 years) underwent neuropsychological tests (structural MRI, FDG-PET, and Florbetapir-PET) and were dichotomized into positive or negative independently for each neuroimaging biomarker. Demographic, neuropsychological, and neuroimaging data were compared between positive and negative subgroups. The MRI-positive subgroup had lower executive performances and mixed patterns of lower volume and metabolism in AD-characteristic regions and in the prefrontal cortex. The FDG-positive subgroup showed only hypometabolism, predominantly in AD-sensitive areas extending to the whole neocortex, compared with the FDG-negative subgroup. The amyloid-positive subgroup was older and included more APOE 4 carriers compared with the amyloidnegative subgroup. When considering MRI and/or FDG biomarkers together (i.e., the neurodegeneration-positive), there was a trend for an inverse relationship with A␤ deposition such that those with neurodegeneration tended to show less A␤ deposition and the reverse was true as well. Our findings suggest that: (1) MRI and FDG biomarkers provide complementary rather than redundant information and (2) relatively young cognitively normal elders tend to have either neurodegeneration or A␤ deposition, but not both, suggesting additive rather than sequential/causative links between AD neuroimaging biomarkers at this age. Key words: Alzheimer's disease; amyloid; biomarkers; FDG; MRI; PET Significance StatementNeuroimaging biomarkers are included in the recent research criteria for preclinical Alzheimer's disease (AD). However, how to use these biomarkers is still being debated, especially regarding their sequence. Our findings suggest that MRI and FDG-PET biomarkers should be used in combination, offering an additive contribution instead of reflecting the same process of neurodegeneration. Moreover, the present study also challenges the hierarchical use of the neuroimaging biomarkers in preclinical AD because it suggests that the neurodegeneration observed in this population is not due to ␤-amyloid deposition. Rather, our results suggest that ␤-amyloid-and tau-related pathological processes may interact but not necessarily appear in a systematic sequence.

We found overall valuable diagnostic performances for FDG PET against reference criteria. Standardized FDG uptake criteria are needed to optimize these diagnostic performances.

Among all tested (18)F-FDG PET/CT methods, the aortic to blood pool SUVmax ratio outperformed the liver and lung ratios. We suggest the use of this ratio for the assessment of aortic inflammation in GCA patients.

Two profiling floats, equipped with nitrate concentration sensors were deployed in the northwestern Mediterranean from summer 2012 to summer 2013. Satellite ocean color data were extracted to evaluate surface chlorophyll concentration at float locations. Time series of mixed layer depths and nitrate and chlorophyll concentrations were analyzed to characterize the interplay between the physical-chemical and biological dynamics in the area. Deep convection (mixed layer depth > 1000 m) was observed in January-February, although high-nitrate surface concentrations could be already observed in December. Chlorophyll increase is observed since December, although high values were observed only in March. The early nitrate availability in subsurface layers, which is likely due to the permanent cyclonic circulation of the area, appears to drive the bloom onset. The additional nitrate supply associated to the deep convection events, although strengthening the overall nitrate uptake, seems decoupled of the December increase of chlorophyll.

Abnormal PET findings are associated with a substantially increased final diagnostic rate in FUO. Consequently, FDG PET could be considered for inclusion in the first-line diagnostic work-up of FUO. Further randomized prospective studies with standardized FDG PET procedures are warranted to confirm this first-line position.

The ε4 allele of the apolipoprotein E (APOE4) is associated with an increased risk of developing Alzheimer's disease (AD). Hence, several studies have compared the brain characteristics of APOE4 carriers versus non-carriers in presymptomatic stages to determine early AD biomarkers. The present review provides an overview on APOE4-related brain changes in cognitively normal individuals, focusing on the main neuroimaging biomarkers for AD, i.e. cortical beta-amyloid (Aβ) deposition, hypometabolism and atrophy. The most consistent findings are observed with Aβ deposition as most studies report significantly higher cortical Aβ load in APOE4 carriers compared with non-carriers. Fluorodeoxyglucose-positron emission tomography studies are rare and tend to show hypometabolism in brain regions typically impaired in AD. Structural magnetic resonance imaging findings are the most numerous and also the most discrepant, showing atrophy in AD-sensitive regions in some studies but contradicting results as well. Altogether, this suggests a graded effect of APOE4, with a predominant effect on Aβ over brain structure and metabolism. Multimodal studies confirm this view and also suggest that APOE4 effects on brain structure and function are mediated by both Aβ-dependent and Aβ-independent pathological processes. Neuroimaging studies on asymptomatic APOE4 carriers offer relevant information to the understanding of early pathological mechanisms of the disease, although caution is needed as to whether APOE4 effects reflect AD pathological processes, and are representative of these effects in non-carriers.

In 2013, as part of the French NAOS (Novel Argo Oceanic observing System) program, five profiling floats equipped with nitrate sensors (SUNA‐V2) together with CTD and bio‐optical sensors were deployed in the Mediterranean Sea. At present day, more than 500 profiles of physical and biological parameters were acquired, and significantly increased the number of available nitrate data in the Mediterranean Sea. Results obtained from floats confirm the general view of the basin, and the well‐known west‐to‐east gradient of oligotrophy. At seasonal scale, the north western Mediterranean displays a clear temperate pattern sustained by both deep winter mixed layer and shallow nitracline. The other sampled areas follow a subtropical regime (nitracline depth and mixed layer depth are generally decoupled). Float data also permit to highlight the major contribution of high‐frequency processes in controlling the nitrate supply during winter in the north western Mediterranean Sea and in altering the nitrate stock in subsurface in the eastern basin.