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Three-dimensional flow characterization using vector pattern matching
This paper describes a novel method for regional characterization of three-dimensional vector fields using a pattern matching approach. Given a three-dimensional vector field, the goal is to automatically locate, identify, and visualize a selected set of classes of structures or features. Rather than analytically defining the properties that must be fulfilled in a region in order to be classified
Kinematics of the heart : Strain-rate imaging from time-resolved three-dimensional phase contrast MRI
A four-dimensional mapping (three spatial dimensions + time) of myocardial strain-rate would help to describe the mechanical properties of the myocardium, which affect important physiological factors such as the pumping performance of the ventricles. Strain-rate represents the local instantaneous deformation of the myocardium and can be calculated from the spatial gradients of the velocity field.
Influence of respiration on myocardial signal intensity
Echocardiographic quantification of myocardial perfusion after IV contrast is possible, based on the intensity of the received intermittent second harmonic signal. To investigate the influence of respiration on the intensity of myocardial signals, we examined nine patients with normal coronary angiograms. At baseline, end-expiratory and end-inspiratory images were obtained in broadband radiofreque
Is there a change in myocardial nonlinearity during the cardiac cycle?
The distortion of a sound wave during propagation results in progressive transfer of the energy from fundamental to higher harmonics, and is dependent on the nonlinearity of the medium. We studied if relative changes in acoustical nonlinearity occur in healthy myocardium during the cardiac cycle. Radiofrequency data were acquired from transthoracic echocardiography (2.5 and 3.5 MHz), parasternal l
Quantitation of left-ventricular asynergy by cardiac ultrasound
The clinical evaluation of regional delays in myocardial motion (myocardial asynchrony) has proved problematic, yet it remains an important functional parameter to evaluate. Prior attempts to quantify regional asynergy have met with limited success, often thwarted by the low temporal resolution of imaging-system data acquisition. If a delay in onset of motion of 30-40 msec is clinically important
Segmentation of echocardiographic image sequences using spatio-temporal information
This paper describes a new method for improving border detection in image sequences by including both spatial and temporal information. The method is based on three dimensional quadrature filters for estimating local orientation. A simplification that gives a significant reduction in computational demand is also presented. The border detection framework is combined with a segmentation algorithm ba
Tensor field visualisation using adaptive filtering of noise fields combined with glyph rendering
While many methods exist for visualising scalar and vector data, visualisation of tensor data is still troublesome. We present a method for visualising second order tensors in three dimensions using a hybrid between direct volume rendering and glyph rendering. An overview scalar field is created by using three-dimensional adaptive filtering of a scalar field containing noise. The filtering process
Learning from Failure - When Agency Could Not Overcome Structure
Mesoporous silica as a matrix for photocatalytic titanium dioxide nanoparticles : lipid membrane interactions
In the present study, we investigate the combined interaction of mesoporous silica (SiO2) and photocatalytic titanium dioxide (TiO2) nanoparticles with lipid membranes, using neutron reflectometry (NR), cryo-transmission electron microscopy (cryo-TEM), fluorescence oxidation assays, dynamic light scattering (DLS), and ζ-potential measurements. Based on DLS, TiO2 nanoparticles were found to display
Fluid flow and heat transfer in a rectangular ribbed channel with a hierarchical design for turbine blade internal cooling
For internal cooling of a turbine blade, various advanced rib turbulators can markedly contribute to the heat transfer enhancement while suffering a great increase in pressure loss. In those designs, ribs with the same configuration are periodically and evenly mounted on the channel wall. In this context, this work proposes a hierarchical design concept to optimize the rib arrangement with the des
Big Science and Research Infrastructures in Europe : Conclusions and outlook
Big Science and Research Infrastructures are ostensibly important features of contemporary European science and innovation policy. But while we can look back on half a century of attention to Big Science, in political debate as well as scholarly studies of depth and breadth, Research Infrastructures is a more recent phenomenon. In this concluding chapter, we summarize the findings and the contribu
SHG Imaging for Tissue Engineering Applications
Treatment of lost tissue oen relies on transplantations, either of donor or of autologous tissue. Both alternatives have limitations; there is for example a limited supply of donor transplants, which also require immunosuppression therapy with possible side eects. Transplanted autologous tissue may lack some of the functions of the original tissue and the procedure may also introduce complications
Navigating Human Rights, Feminism, and History : Egyptian Feminist Activists’ Demands for Constitutional Equality, 2012–2014
This article analyzes the efforts of Egyptian feminist activists to insert gender equality in the country’s post-revolutionary constitutions in 2012 and 2014. While the literature on women’s political role during this period provides insights into exclusionary gender practices and conditions for bargaining power structures, this study contributes with a conceptual analysis of how feminist activist
The Relationship Between Political Attitudes and Political Participation: Evidence from Monozygotic Twins in the United States, Sweden, Germany, and Denmark
Introduction to the special issue from personality to politics
Structural basis of activation and antagonism of receptor signaling mediated by interleukin-27
Interleukin-27 (IL-27) uniquely assembles p28 and EBI3 subunits to a heterodimeric cytokine that signals via IL-27Rα and gp130. To provide the structural framework for receptor activation by IL-27 and its emerging therapeutic targeting, we report here crystal structures of mouse IL-27 in complex with IL-27Rα and of human IL-27 in complex with SRF388, a monoclonal antibody undergoing clinical trial
Parental transmission and the importance of the (non-causal) effects of education on political engagement: Missing the forest for the trees
Dynamical Modeling of Cloud Applications for Runtime Performance Management
Cloud computing has quickly grown to become an essential component in many modern-day software applications. It allows consumers, such as a provider of some web service, to quickly and on demand obtain the necessary computational resources to run their applications. It is desirable for these service providers to keep the running cost of their cloud application low while adhering to various perform
Spatial variations in financial constraints of SMEs—evidence from firm-level estimates of investment-cash flow sensitivities in Sweden
It is well established that there is uneven availability of credit across space, in particular for SMEs. The evidence on whether this translates into differences in actual business investments remains scarce. We assess this question by using firm-level data for Swedish firms and estimate the extent to which the average investment-cash flow sensitivities of firms vary across the urban–rural hierarc