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Überatlas : Fast and robust registration for multi-atlas segmentation

Multi-atlas segmentation has become a frequently used tool for medical image segmentation due to its outstanding performance. A computational bottleneck is that all atlas images need to be registered to a new target image. In this paper, we propose an intermediate representation of the whole atlas set – an überatlas – that can be used to speed up the registration process. The representation consis

Platelet-derived growth factor-BB has neurorestorative effects and modulates the pericyte response in a partial 6-hydroxydopamine lesion mouse model of Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease where the degeneration of the nigrostriatal pathway leads to specific motor deficits. There is an unmet medical need for regenerative treatments that stop or reverse disease progression. Several growth factors have been investigated in clinical trials to restore the dopaminergic nigrostriatal pathway damaged in PD. Platelet-derived growth fac

Implementation and validation of an environmental feedback pool fire model based on oxygen depletion and radiative feedback in FDS

This paper has been aimed at implementing and validating a simplified environmental feedback fire model in FDS as a complement to more advanced pyrolysis models. The two main means of environmental feedback have been identified as the oxygen concentration close to the fuel base and the radiative feedback from the surrounding obstructions and smoke layer. The oxygen concentration at the fuel base h

Long-term effective population size dynamics of an intensively monitored vertebrate population

Long-term genetic data from intensively monitored natural populations are important for understanding how effective population sizes (N e) can vary over time. We therefore genotyped 1622 common buzzard (Buteo buteo) chicks sampled over 12 consecutive years (2002-2013 inclusive) at 15 microsatellite loci. This data set allowed us to both compare single-sample with temporal approaches and explore te

Antithetic sampling for sequential Monte Carlo methods with application to state-space models

In this paper, we cast the idea of antithetic sampling, widely used in standard Monte Carlo simulation, into the framework of sequential Monte Carlo methods. We propose a version of the standard auxiliary particle filter where the particles are mutated blockwise in such a way that all particles within each block are, first, offspring of a common ancestor and, second, negatively correlated conditio

Simulating cross-shore material exchange at decadal scale. Theory and model component validation

A model is developed to simulate the cross-shore (CS) exchange of sand and the resulting profile response at decadal scale to be used in regional coastal evolution models. The CS model consists of modules for calculating dune erosion and overwash, wind-blown sand transport, and bar-berm material exchange. The sand transport equations included in these modules are formulated based on relevant physi

Most patients with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency develop pathological or subnormal retinal function

Aim: There have been few studies on long-term electroretinographic findings in patients with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD). This study correlated long-term electroretinographic findings with age, metabolic control and clinical symptoms. Methods: We examined 12 Swedish patients with LCHADD. Visual acuity testing, fundus examinations, optical coherence tomography and

Interface dynamics and crystal phase switching in GaAs nanowires

Controlled formation of non-equilibrium crystal structures is one of the most important challenges in crystal growth. Catalytically grown nanowires are ideal systems for studying the fundamental physics of phase selection, and could lead to new electronic applications based on the engineering of crystal phases. Here we image gallium arsenide (GaAs) nanowires during growth as they switch between ph

Characterization of total ecosystem-scale biogenic VOC exchange at a Mediterranean oak–hornbeam forest

Recently, the number and amount of biogenically emitted volatile organic compounds (VOCs) has been discussed in great detail. Depending on the ecosystem, the published number varies between a dozen and several hundred compounds. We present ecosystem exchange fluxes from a mixed oak–hornbeam forest in the Po Valley, Italy. The fluxes were measured by a proton transfer reaction-time-of-flight (PTR-T

Mass-flowering crops dilute pollinator abundance in agricultural landscapes across Europe

Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were

Loss of genetic diversity and increased embryonic mortality in non-native lizard populations

Many populations are small and isolated with limited genetic variation and high risk of mating with close relatives. Inbreeding depression is suspected to contribute to extinction of wild populations, but the historical and demographic factors that contribute to reduced population viability are often difficult to tease apart. Replicated introduction events in non-native species can offer insights

Characterization and reconstruction of VOG noise with power spectral density analysis

Characterizing noise in eye movement data is important for data analysis, as well as for the comparison of research results across systems. We present a method that characterizes and reconstructs the noise in eye movement data from video-oculography (VOG) systems taking into account the uneven sampling in real recordings due to track loss and inherent system features. The proposed method extends t

Review on Dimensionless Numbers Relevant for Polymer Electrolyte Fuel Cells

With the concern about global warming, air pollution and energy security, the prospect of using polymer electrolyte fuel cells (PEFCs) in future sustainable and renewable energy conversion systems has achieved substantial momentum. Dimensionless numbers can be determined before construction of a model is started, to make simple estimations on the transport processes, for example, within the porous

Impact on Diffusion Parameters Computation in Gas Diffusion Layers, Considering the Land/Channel Region, Using the Lattice Boltzmann Method

Diffusion phenomena through the gas diffusion layer (GDL) at the microscale are one of the most complex physical phenomena to be described in proton exchange fuel cell (PEFC) numerical models. Predicting transport parameter behavior in GDLs is a valuable stage to propose micro-architectural designs, which can improve the efficiency and performance of fuel cells (FCs). The purpose of this paper is

The Image is Openness, The Practice is Data

The paper argues for the importance of seeing just how we conceptualise digital phenomena in relation to how the regulatory discourses. The Internet used to be an “information superhighway”, a “cyberspace”, or a “world wide web” often described as an empowering structure, that now has transformed to be understood in terms of “layers”, a generator of big data for a number of “platform” ventures and