The potential of micromorphology for interpreting sedimentation processes in wetland sites: a case study of a Late Bronze-early Iron Age lakeshore settlement at Lake Luokesa (Lithuania)

Lake Luokesa lies in the eastern part of Lithuania and is part of a region of lakes formed by the Scandinavian ice-sheet and its melt waters during the last glaciation. During the Late Bronze-Early Iron Age transition, between 625 and 535cal BC, a lakeside settlement with an onshore palisade was built on the platform of a carbonate bank. A total of five profiles, each comprising an organic occupation layer and lake sediments at its bottom and top, were examined micromorphologically. In this paper, natural and anthropogenic processes that led to the formation of the individual layers are presented; their possible origins are reconstructed and then discussed and compared to lakeside settlements of the circum-alpine region. This includes the emergence of lake marl, accumulation of organic layers in the settlement area as well as their decomposition, erosion and trampling features and inwash of sand through runoff from the hinterland. Due to the accumulation of the up to 60cm thick culture layers in waterlogged environments, indications of seasonal deposition cycles could be identified

Micromorphological indicators for degradation processes in archaeological bone from temperate European wetland sites

Micromorphological investigations of archaeological bones make it possible to study decay processes and the associated depositional environment in one go. A selection of micromorphological thin sections from soil samples from three wetland sites in Switzerland, The Netherlands and Norway that contained bone fragments were studied. The goal was to investigate the type and the timing of decay processes to better understand the taphonomy of bones in such sites. Using optical microscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), a range of biological decay processes and chemical/mineralogical transformations were observed. In two of the sites e Zug-Riedmatt in Switzerland and Hazendonk in The Netherlands e a relatively short exposure to adverse conditions must have occurred: Some of the bones from Zug-Riedmatt show localized collagen decay related to exposure to fresh ashes; others show cyanobacterial tunnelling related to submersion in shallow, clear water. In Hazendonk, bone fragments and fish scales apparently have first been exposed to bacterial decay related to putrefaction. Subsequently, alternations between wet and dry conditions resulted in the dissolution of some of the bone mineral and the formation of Ca, Fe(III) phosphates, probably mitridatite. Fungal decay caused extensive tunnelling of bone and fish scales as well as the secondary phosphates. These processes apparently ended when the bone-rich layer became permanently waterlogged and anoxic. In Stavanger, bone mineral is transformed into mitridatite and possibly other Ca Fe(III) phosphates. Indications that the redox conditions are variable at present suggest that these processes are still active. ©submittedVersio

Feeding the crusades: archaeobotany, animal husbandry and livestock alimentation on the Baltic frontier

The integrated results of micromorphology, plant macrofossil, pollen, phytolith, and non-pollen palynomorph analyses represent an important study of two thirteenth-century Teutonic Order castles at Karksi (Livonia), and Elbląg (Prussia). The research examines deposits that formed during the period of active crusading. At Karksi, the investigation of a midden and of the organic-rich sediment beneath allows the diachronic use of this area to be understood. Freshwater aquatic indicators are consistent with the occurrence of shallow stagnant water, as also suggested by a waterlaid pond sediment identified in thin-section. Coprophilous spore taxa suggest the use of the pond as a watering hole. Plant macrofossils from the midden represent a range of habitats, mostly from wet/damp areas, as well as pastures and meadows, and also woodlands. Fragments of millet are embedded within herbivore dung in thin-section showing the use of this grain as fodder. At Elbląg, parasite ova may derive from animal feces as they also occur in the dung observed in thin-section, and a range of coprophilous fungal spore taxa were extracted. The results reveal information about the range of livestock that the Teutonic Knights kept, whereabouts within the castles the animals were stabled, and what fodder was used

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Brain multiplexes reveal morphological connectional biomarkers fingerprinting late brain dementia states

Accurate diagnosis of mild cognitive impairment (MCI) before conversion to Alzheimer’s disease (AD) is invaluable for patient treatment. Many works showed that MCI and AD affect functional and structural connections between brain regions as well as the shape of cortical regions. However, ‘shape connections’ between brain regions are rarely investigated -e.g., how morphological attributes such as cortical thickness and sulcal depth of a specific brain region change in relation to morphological attributes in other regions. To fill this gap, we unprecedentedly design morphological brain multiplexes for late MCI/AD classification. Specifically, we use structural T1-w MRI to define morphological brain networks, each quantifying similarity in morphology between different cortical regions for a specific cortical attribute. Then, we define a brain multiplex where each intra-layer represents the morphological connectivity network of a specific cortical attribute, and each inter-layer encodes the similarity between two consecutive intra-layers. A significant performance gain is achieved when using the multiplex architecture in comparison to other conventional network analysis architectures. We also leverage this architecture to discover morphological connectional biomarkers fingerprinting the difference between late MCI and AD stages, which included the right entorhinal cortex and right caudal middle frontal gyrus

Multimodal and Multiscale Deep Neural Networks for the Early Diagnosis of Alzheimer’s Disease using structural MR and FDG-PET images

Alzheimer’s Disease (AD) is a progressive neurodegenerative disease where biomarkers for disease based on pathophysiology may be able to provide objective measures for disease diagnosis and staging. Neuroimaging scans acquired from MRI and metabolism images obtained by FDG-PET provide in-vivo measurements of structure and function (glucose metabolism) in a living brain. It is hypothesized that combining multiple different image modalities providing complementary information could help improve early diagnosis of AD. In this paper, we propose a novel deep-learning-based framework to discriminate individuals with AD utilizing a multimodal and multiscale deep neural network. Our method delivers 82.4% accuracy in identifying the individuals with mild cognitive impairment (MCI) who will convert to AD at 3 years prior to conversion (86.4% combined accuracy for conversion within 1–3 years), a 94.23% sensitivity in classifying individuals with clinical diagnosis of probable AD, and a 86.3% specificity in classifying non-demented controls improving upon results in published literature

The impact of PICALM genetic variations on reserve capacity of posterior cingulate in AD continuum

Phosphatidylinositolbinding clathrin assembly protein (PICALM) gene is one novel genetic player associated with late-onset Alzheimer’s disease (LOAD), based on recent genome wide association studies (GWAS). However, how it affects AD occurrence is still unknown. Brain reserve hypothesis highlights the tolerant capacities of brain as a passive means to fight against neurodegenerations. Here, we took the baseline volume and/or thickness of LOAD-associated brain regions as proxies of brain reserve capacities and investigated whether PICALM genetic variations can influence the baseline reserve capacities and the longitudinal atrophy rate of these specific regions using data from Alzheimer’s Disease Neuroimaging Initiative (ADNI) dataset. In mixed population, we found that brain region significantly affected by PICALM genetic variations was majorly restricted to posterior cingulate. In sub-population analysis, we found that one PICALM variation (C allele of rs642949) was associated with larger baseline thickness of posterior cingulate in health. We found seven variations in health and two variations (rs543293 and rs592297) in individuals with mild cognitive impairment were associated with slower atrophy rate of posterior cingulate. Our study provided preliminary evidences supporting that PICALM variations render protections by facilitating reserve capacities of posterior cingulate in non-demented elderly