Does global warming favour the occurrence of extreme floods in European Alps? First evidences from a NW Alps proglacial lake sediment record

Flood hazard is expected to increase in the context of global warming. However, long time-series of climate and gauge data at high-elevation are too sparse to assess reliably the rate of recurrence of such events in mountain areas. Here paleolimnological techniques were used to assess the evolution of frequency and magnitude of flash flood events in the North-western European Alps since the Little Ice Age (LIA). The aim was to document a possible effect of the post-19(th) century global warming on torrential floods frequency and magnitude. Altogether 56 flood deposits were detected from grain size and geochemical measurements performed on gravity cores taken in the proglacial Lake Blanc (2170 m a.s.l., Belledonne Massif, NW French Alps). The age model relies on radiometric dating (Cs-137 and Am-241), historic lead contamination and the correlation of major flood- and earthquake-triggered deposits, with recognized occurrences in historical written archives. The resulting flood calendar spans the last ca 270 years (AD 1740-AD 2007). The magnitude of flood events was inferred from the accumulated sediment mass per flood event and compared with reconstructed or homogenized datasets of precipitation, temperature and glacier variations. Whereas the decennial flood frequency seems to be independent of seasonal precipitation, a relationship with summer temperature fluctuations can be observed at decadal timescales. Most of the extreme flood events took place since the beginning of the 20(th) century with the strongest occurring in 2005. Our record thus suggests climate warming is favouring the occurrence of high magnitude torrential flood events in high-altitude catchments

Awareness of cognitive decline trajectories in asymptomatic individuals at risk for AD

Background: Lack of awareness of cognitive decline (ACD) is common in late-stage Alzheimer’s disease (AD). Recent studies showed that ACD can also be reduced in the early stages. Methods: We described different trends of evolution of ACD over 3 years in a cohort of memory-complainers and their association to amyloid burden and brain metabolism. We studied the impact of ACD at baseline on cognitive scores’ evolution and the association between longitudinal changes in ACD and in cognitive score. Results: 76.8% of subjects constantly had an accurate ACD (reference class). 18.95% showed a steadily heightened ACD and were comparable to those with accurate ACD in terms of demographic characteristics and AD biomarkers. 4.25% constantly showed low ACD, had significantly higher amyloid burden than the reference class, and were mostly men. We found no overall effect of baseline ACD on cognitive scores’ evolution and no association between longitudinal changes in ACD and in cognitive scores. Conclusions: ACD begins to decrease during the preclinical phase in a group of individuals, who are of great interest and need to be further characterized. Trial registration: The present study was conducted as part of the INSIGHT-PreAD study. The identification number of INSIGHT-PreAD study (ID-RCB) is 2012-A01731-42

Retrospective French nationwide survey of childhood aggressive vascular anomalies of bone, 1988-2009

<p>Abstract</p> <p>Objective</p> <p>To document the epidemiological, clinical, histological and radiological characteristics of aggressive vascular abnormalities of bone in children.</p> <p>Study design</p> <p>Correspondents of the French Society of Childhood Malignancies were asked to notify all cases of aggressive vascular abnormalities of bone diagnosed between January 1988 and September 2009.</p> <p>Results</p> <p>21 cases were identified; 62% of the patients were boys. No familial cases were observed, and the disease appeared to be sporadic. Mean age at diagnosis was 8.0 years [0.8-16.9 years]. Median follow-up was 3 years [0.3-17 years]. The main presenting signs were bone fracture (n = 4) and respiratory distress (n = 7), but more indolent onset was observed in 8 cases. Lung involvement, with lymphangiectasies and pleural effusion, was the most frequent form of extraosseous involvement (10/21). Bisphosphonates, alpha interferon and radiotherapy were used as potentially curative treatments. High-dose radiotherapy appeared to be effective on pleural effusion but caused major late sequelae, whereas antiangiogenic drugs like alpha interferon and zoledrenate have had a limited impact on the course of pulmonary complications. The impact of bisphosphonates and alpha interferon on bone lesions was also difficult to assess, owing to insufficient follow-up in most cases, but it was occasionally positive. Six deaths were observed and the overall 10-year mortality rate was about 30%. The prognosis depended mainly on pulmonary and spinal complications.</p> <p>Conclusion</p> <p>Aggressive vascular abnormalities of bone are extremely rare in childhood but are lifethreatening. The impact of anti-angiogenic drugs on pulmonary complications seems to be limited, but they may improve bone lesions.</p

Low Cognitive Awareness, but Not Complaint, is a Good Marker of Preclinical Alzheimer's Disease

Subjective cognitive decline (SCD) may result from many conditions, including Alzheimer's disease (AD)

Geochemical bias in drill cutting samples versus drill core samples returned from the Reykjanes Geothermal System, Iceland

The wholerock major and trace element composition of drill cutting samples are compared to drill core samples from adjacent depths in the seawater recharged Reykjanes geothermal system in Iceland. The first appearance of alteration minerals and lithologies in drill cutting samples is a useful tool for interpreting broad subsurface characteristics. However, use of drill cutting samples for determining igneous affinity and elemental exchanges during hydrothermal alteration is problematic. Samples recovered from immediately above and below the cored intervals in wells RN-17B and RN-30 demonstrate that drill-cutting samples are biased towards preservation of least altered primary igneous minerals and more resistant alteration minerals, including albite, quartz, and epidote, with preferential loss of finer-grained and less resistant minerals including chlorite and actinolite. This selective recovery obscures elemental exchanges resulting from hydrothermal alteration processes. For some elements, compositional variations (enrichments and depletions) measured from 9.5 m of core exceeds that observed in ~3000 m of cutting analyses. Concentration ratios of hydrothermally immobile elements including Zr, Nb, V, Y, HREE, Hf, Ta and Th in deep (&gt;2245 m) spot drill core samples record bimodal, trace element-enriched and trace element-depleted precursor compositions similar to subaerial Reykjanes Peninsula basalts. The same elements in nearly 3000 m of drill cutting samples from well RN-17 overwhelmingly reflect the more common trace element-enriched igneous precursor, demonstrating that mixing of drill cutting samples obscures details of their igneous affinity. A new and different drill rig was used to deepen well RN-17 below 2266 m in a sidetrack hole (RN-17ST), which resulted in a change in drilling conditions, accompanied with an increased well deviation angle from ~0° to ~4°. Wholerock geochemical results for drill cutting samples from RN-17ST are homogenous for virtually every element; suggesting the change in drilling conditions resulted in extreme mixing of the drill cuttings. Anomalously high concentrations of Cu, Ni, Cr and Ta in some drill cutting samples likely reflects contamination of drill cutting samples by metal alloys used in drill bits and drill collars or more resistant spinel and sulfide phases

Vignols (Léon). — La Course maritime, ses conséquences économiques et sociales et internationales. 1927

Revillon A. Vignols (Léon). — La Course maritime, ses conséquences économiques et sociales et internationales. 1927. In: Revue d'histoire moderne, tome 2 N°12,1927. p. 478

Vignols (Léon). — La Course maritime, ses conséquences économiques et sociales et internationales. 1927

Revillon A. Vignols (Léon). — La Course maritime, ses conséquences économiques et sociales et internationales. 1927. In: Revue d'histoire moderne, tome 2 N°12,1927. p. 478