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Cortical volumetry and longitudinal cognitive changes in Parkinson’s disease: insights from the COPPADIS cohortNARA Subscribed
Cognitive decline is a major non-motor symptom in Parkinson’s disease (PD), often linked to brain atrophy. This study examines the relationship between cortical atrophy and age groups in predicting cognitive decline in PD over five years. 188 PD patients from the COPPADIS cohort were stratified by age: young (30–55 years, N = 47), middle-aged (56–65 years, N = 59), and older adults (66–75 years, N = 82). Baseline cortical volu...
Sediment-redox dynamics in an oligotrophic deep-water lake in Tierra del Fuego: insights from Fe isotopesNARA Subscribed
For long time in the history of Earth, ferruginous conditions governed the oceans. With the rise of oxygen during the Proterozoic era and the subsequent evolution of living organisms, worldwide deposition of iron formations occurred. These sedimentary units reveal the transition into oxic oceans, passing by local and transitory euxinic conditions, especially in coastal shelves. Constraining the iron cycle and the biogeochemica...
Summary An unsuspected biomineralization process, which produces intracellular inclusions of amorphous calcium carbonate (ACC), was recently discovered in unicellular eukaryotes. These mineral inclusions, called micropearls , can be highly enriched with other alkaline‐earth metals (AEM) such as Sr and Ba. Similar intracellular inclusions of ACC have also been observed in prokaryotic organisms. These comparable biomineralizatio...
Numerical simulations show that the Storegga tsunami (∼8 150 cal a BP) penetrated into fjords and sounds along the Norwegian coast because of its large wavelengths of about 600–800 km. Despite this, deposits from the tsunami have not previously been reported from the innermost fjord district, probably because suitable sedimentary archives are lacking in the steep fjord landscape. Here we describe a persistent and well‐defined...
Lake‐level changes in central Patagonia (Argentina): crossing environmental thresholds for Lateglacial and Holocene human occupationNARA Subscribed
The role and extent of climate as a cause of the expansion and decline of human cultures is still debatable. It is clear, however, that human–environment interactions are enhanced and interplay more closely in climatically sensitive areas such as around hydrologically closed basins. Lago Cardiel is located at 49° S in the very arid rain shadow east of the Andes, providing an exceptionally receptive system to changes in hydrolo...
Holocene climatic fluctuations and positioning of the Southern Hemisphere westerlies in Tierra del Fuego (54° S), PatagoniaNARA Subscribed
Recent advances in the chronology and the palaeoclimatic understanding of Antarctic ice core records point towards a larger heterogeneity of latitudinal climate fluctuations than previously thought. Thus, realistic palaeoclimate reconstructions rely in the development of a tight array of well‐constrained records with a dense latitudinal coverage. Climatic records from southernmost South America are critical cornerstones to lin...
Climate change in lowland Central America during the late deglacial and early HoloceneNARA Subscribed
The transition from arid glacial to moist early Holocene conditions represented a profound change in northern lowland Neotropical climate. Here we report a detailed record of changes in moisture availability during the latter part of this transition (∼11 250 to 7500 cal. yr BP) inferred from sediment cores retrieved in Lake Petén Itzá, northern Guatemala. Pollen assemblages demonstrate that a mesic forest had been largely esta...
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