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Histogram analysis of tensor-valued diffusion MRI in meningiomas : Relation to consistency, histological grade and type

BACKGROUND: Preoperative radiological assessment of meningioma characteristics is of value for pre- and post-operative patient management, counselling, and surgical approach.PURPOSE: To investigate whether tensor-valued diffusion MRI can add to the preoperative prediction of meningioma consistency, grade and type.MATERIALS AND METHODS: 30 patients with intracranial meningiomas (22 WHO grade I, 8 W

Estimating nonlinear chirp modes exploiting sparsity

The decomposition of nonlinear chirp modes is a challenging task, typically requiring prior knowledge of the number of modes a signal contains. In this work, we present a greedy nonlinear chirp mode estimation (NCME) technique that forms the used decomposition basis from the signal itself, using an arctangent demodulation technique. The resulting decomposition is formed by considering the residual

Redox geochemistry of the red ‘orthoceratite limestone’ of Baltoscandia : Possible linkage to mid-Ordovician palaeoceanographic changes

The orthoceratite limestone of the Ordovician epicontinental sea of Baltoscandia is one of the oldest Phanerozoic examples of pelagic marine red beds (MRBs). Being enriched in authigenic haematite, MRBs are considered to be sensitive palaeoceanographic redox indicators. In this paper, the origin of the reddening of the Ordovician MRBs and its timing and redox conditions were addressed at two secti

Effects of red blood cells with reduced deformability on cerebral blood flow and vascular water transport: measurements in rats using time-resolved pulsed arterial spin labelling at 9.4 T

BackgroundOur aim was to introduce damaged red blood cells (RBCs) as a tool for haemodynamic provocation in rats, hypothesised to cause decreased cerebral blood flow (CBF) and prolonged water capillary transfer time (CTT), and to investigate whether expected changes in CBF could be observed and if haemodynamic alterations were reflected by the CTT metric.MethodsDamaged RBCs exhibiting a mildly red

Complex dynamics of water quality mixing in a warm mono-mictic reservoir

Cycling of water quality constituents in lakes is affected by thermal stratification and homo-thermal conditions and other factors such as oligotrophication, eutrophication, and microbial activities. In addition, hydrological variability can cause greater differences in water residence time and cycling of constituents in man-made lakes (reservoirs) than in natural lakes. Thus, investigations are n

Preparation and thermophysical property analysis of nanocomposite phase change materials for energy storage

Paraffin wax and various nanoparticles (CuO, Al2O3 and Fe3O4) were used as matrix and heat conduction enhancer of phase change materials (PCMs), respectively. The dispersant Span 80 was added into the nanocomposite to provide stable PCMs. Based on analyses of melting and freezing curves and infrared thermal imaging tests, the phase change latent heat, viscosity, and thermal conductivity of the nan

Occupation, socioeconomic status and chronic obstructive respiratory diseases – The EpiLung study in Finland, Estonia and Sweden

Objective: To study occupational groups and occupational exposure in association with chronic obstructive respiratory diseases. Methods: In early 2000s, structured interviews on chronic respiratory diseases and measurements of lung function as well as fractional expiratory nitric oxide (FENO) were performed in adult random population samples of Finland, Sweden and Estonia. Occupations were categor

Numerical simulation of a mixed-mode reaction front in a PPC engine

The ignition process, mode of combustion and reaction front propagation in a partially premixed combustion (PPC) engine running with a primary reference fuel (87 vol% iso-octane, 13 vol% n-heptane) were investigated numerically in a large eddy simulation (LES). A one-equation sub-grid scale model coupled to the partially stirred reactor model and a finite rate chemical model were used in LES. Diff

Genremönster i Ministern har ordet : Regeringar rapporterar om bolag med statligt ägande

The article deals with the genre consolidated government accounts of state-owned enterprises in Finland and Sweden. More specifically, the study is focused on the subgenre the foreword of the responsible minister, which we label Statement from the Minister in analogy with Statement from the CEO in the related genre corporate annual reports. The primary data consist of Statement from the Minister iThe article deals with the genre consolidated government accounts of state-owned enter-prises in Finland and Sweden. More specifically, the study is focused on the subgenre the foreword of the responsible minister, which we label Statement from the Minister in anal-ogy with Statement from the CEO in the related genre corporate annual reports. The pri-mary data consist of Statement from the Ministe

A Ca. 2.25 Ga mafic dyke swarm discovered in the Bastar craton, Central India : Implications for a widespread plume-generated large Igneous Province (LIP) in the Indian shield

A precise U–Pb baddeleyite age (2251 ± 4 Ma) has been obtained for an ENE-trending dyke exposed near the Chhura region of the Bastar craton, and additional dykes of similar trend are also reported from other parts of the northern Bastar craton such as in the Dongergarh and Pakhanjore areas. We propose a new widespread ENE-trending ca. 2.25 Ga Chhura mafic dyke swarm in the Bastar craton, which rep

Identification of a new 485 Ma post-orogenic mafic dyke swarm east of the Pan-African Saldania-Gariep Belt of South Africa

Western South Africa between Cape Town and the Namibian border hosts many dyke swarms that strike broadly to the NW and NNW, towards the reconstructed plume-centre of the c. 130 Ma Parana-Etendeka Large Igneous Province (LIP) but are undated. U-Pb ID-TIMS age determinations on baddeleyite from two NNW-striking dykes (~100 km long) parallel to the Namaqualand coast yield 487 ± 8 Ma and 482 ± 7 Ma a

Lifetime measurements of excited states in 169,171,173Os : Persistence of anomalous B(E2) ratios in transitional rare earth nuclei in the presence of a decoupled i13/2 valence neutron

Lifetimes of low-lying excited states in the νi13/2+ bands of the neutron-deficient osmium isotopes 169,171,173Os have been measured for the first time using the recoil-distance Doppler shift and recoil-isomer tagging techniques. An unusually low value is observed for the ratio B(E2;21/2+→17/2+)/B(E2;17/2+→13/2+) in 169Os, similar to the “anomalously” low values of the ratio B(E2;41+→21+)/B(E2;21+

Differential trajectories of hypometabolism across cognitively-defined Alzheimer's disease subgroups

Disentangling biologically distinct subgroups of Alzheimer's disease (AD) may facilitate a deeper understanding of the neurobiology underlying clinical heterogeneity. We employed longitudinal [18F]FDG-PET standardized uptake value ratios (SUVRs) to map hypometabolism across cognitively-defined AD subgroups. Participants were 384 amyloid-positive individuals with an AD dementia diagnosis from ADNI