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Physical barriers and environmental gradients cause spatial and temporal genetic differentiation of an extensive algal bloom

Aim: To test if a phytoplankton bloom is panmictic, or whether geographical and environmental factors cause spatial and temporal genetic structure. Location: Baltic Sea. Method: During four cruises, we isolated clonal strains of the diatom Skeletonema marinoi from 9 to 10 stations along a 1132 km transect and analysed the genetic structure using eight microsatellites. Using F-statistics and Bayesi

Panel bootstrap tests of slope homogeneity

This paper proposes two bootstrap-based tests that can be used to infer whether the individual slopes in a panel regression model are homogenous. The first test is suitable when wanting to infer the null of homogeneity versus the general alternative, while the second is suitable when wanting to infer the units of the panel that can be pooled. Both approaches are shown to be asymptotically valid, a

The polysemy of ‘fallacy’—or ‘bias’, for that matter

Starting with a brief overview of current usages (Sect. 2), this paper offers some constituents of a use-based analysis of ‘fallacy’, listing 16 conditions that have, for the most part implicitly, been discussed in the literature (Sect. 3). Our thesis is that at least three related conceptions of ‘fallacy’ can be identified. The 16 conditions thus serve to “carve out” a semantic core and to distin

Global socio-technical regimes

This paper addresses the question why socio-technical transitions followsimilar trajectories in various parts of the world, even though the relevant material preconditions and institutional contexts vary greatly between different countries. It takes a critical stance on the implicit methodological nationalism in transition studies’ socio-technical regime concept and proposes an alternative ‘global

Wake analysis of drag components in gliding flight of a jackdaw (Corvus monedula) during moult

To maintain the quality of the feathers, birds regularly undergo moult. It is widely accepted that moult affects flight performance, but the specific aerodynamic consequences have received relatively little attention. Here we measured the components of aerodynamic drag from the wake behind a gliding jackdaw (Corvus monedula) at different stages of its natural wing moult. We found that span efficie

Cognitive function in stroke survivors : A 10-year follow-up study

OBJECTIVES: Post-stroke cognitive impairment (PSCI) has considerable impact on patients and society. However, long-term studies on PSCI are scarce and may be influenced by assessment methods and selection bias. We aimed to (i) assess the prevalence of long-term PSCI; (ii) compare two common cognitive assessment instruments; and (iii) compare cognitive function of long-term stroke survivors with no

Temporal and spatial characteristics of the area at risk investigated using computed tomography and T1-weighted magnetic resonance imaging

AIMS: Cardiovascular magnetic resonance (CMR) imaging can measure the myocardial area at risk (AAR), but the technique has received criticism for inadequate validation. CMR commonly depicts an AAR that is wider than the infarct, which in turn would require a lateral perfusion gradient within the AAR. We investigated the presence of a lateral perfusion gradient within the AAR and validated CMR meas

Electronic Structures of Free-Standing Nanowires made from Indirect Bandgap Semiconductor Gallium Phosphide

We present a theoretical study of the electronic structures of freestanding nanowires made from gallium phosphide (GaP) - a III-V semiconductor with an indirect bulk bandgap. We consider [001]-oriented GaP nanowires with square and rectangular cross sections, and [111]-oriented GaP nanowires with hexagonal cross sections. Based on tight binding models, both the band structures and wave functions o

The role of executive control in rhythmic timing at different tempi

We investigated the role of attention and executive control in rhythmic timing, using a dual-task paradigm. The main task was a finger tapping task in which participants were asked to tap their index finger in time with metronome sequences. The tempo of the sequences ranged from 600 ms to 3000 ms between each beat. The distractor task, chosen so as to engage executive control processes, was a nove

Diffusion MRI and Poroelastic Biomechanics of Articular Cartilage

Cartilage is a poroelastic material for which application of load leads to fluid flow within and out from the porous solid matrix. The redistribution of fluids is a major factor in determining the mechanical properties and friction coefficients, which consequently depend in a complex way on the details of the load history and geometry. Although current poroelastic models for cartilage generally ag