When do Thick Venture Capital Markets Foster Innovation? An Evolutionary Analysis

In this paper we examine the trade off between different effects of the availability of venture capital on the speed of technological progress in an industry. We consider an evolutionary industry simulation model based on Nelson and Winter (1982) where R&D efforts of an incumbent firm generate technological know-how embodied in key R&D employees, who might use this know-how to found a spinoff of the incumbent. Venture capital is needed to finance a spinoff, and therefore the expected profits from founding a spinoff depend on how easily venture capital can be acquired. Accordingly, thick venture capital markets might have two opposing effects. First, incentives of firms to invest in R&D might be reduced and, second, if spinoff formation results in technological spillovers between the parent firm and the spinoffs, the generation of spinoff firms might positively influence the future efficiency of the incumbent's innovation efforts. We study how this tradeoff influences the effect of venture capital on the innovation expenditures, speed of technological change and the evolution of industry concentration in several scenarios with different industry characteristics.Venture Capital, Technological Progress, R&D Effort, Spinoff, Industry Evolution

Wasser- und Sumpfpflanzen-Funde im nördlichen Sachsen-Anhalt

Es werden Funde von seltenen und gefährdeten Wasser- und Sumpfpflanzen in Fließgewässern, Auengewässern, Altwasserflachseen und Sekundärgewässern (Abgrabungsgewässer, Gräben, Teiche) im Norden von Sachsen-Anhalt dokumentiert. Für Armleuchteralgen-Funde haben Abgrabungsgewässer im Untersuchungsgebiet eine besondere Bedeutung. Wasser- und Sumpfpflanzen (13 Rote Liste-Arten) des Lebensraumtyps 3150 „Natürliche eutrophe Seen mit einer Vegetation des Magnopotamions oder Hydrocharitions“ zeigen in mehreren Gewässern eine gute Wasserqualität an.Remarks on records of rare and endangered water and swamp plants in running waters, in floodplain waters, shallow oxbow lakes and artificial water bodies (mining waters, ditches, ponds) in the north of the federal state Saxony-Anhalt are given. For the records of stoneworts (Charales) mining waters are important. Water and swamp plants (13 species of the Red Data List) of the biotope type „Natural eutrophic lakes with Magnopotamion or Hydrocharition type vegetation: Natura 2000-Code 3150“ are good indicators of a good water quality

Cardiac magnetic resonance T1 and extracellular volume mapping with motion correction and co-registration based on fast elastic image registration

OBJECTIVE: Our aim was to investigate the technical feasibility of a novel motion compensation method for cardiac magntic resonance (MR) T1 and extracellular volume fraction (ECV) mapping. MATERIALS AND METHODS: Native and post-contrast T1 maps were obtained using modified look-locker inversion recovery (MOLLI) pulse sequences with acquisition scheme defined in seconds. A nonrigid, nonparametric, fast elastic registration method was applied to generate motion-corrected T1 maps and subsequently ECV maps. Qualitative rating was performed based on T1 fitting-error maps and overlay images. Local deformation vector fields were produced for quantitative assessment. Intra- and inter-observer reproducibility were compared with and without motion compensation. RESULTS: Eighty-two T1 and 39 ECV maps were obtained in 21 patients with diverse myocardial diseases. Approximately 60% demonstrated clear quality improvement after motion correction for T1 mapping, particularly for the poor-rating cases (23% before vs 2% after). Approximately 67% showed further improvement with co-registration in ECV mapping. Although T1 and ECV values were not clinically significantly different before and after motion compensation, there was improved intra- and inter-observer reproducibility after motion compensation. CONCLUSIONS: Automated motion correction and co-registration improved the qualitative assessment and reproducibility of cardiac MR T1 and ECV measurements, allowing for more reliable ECV mapping

Symmetric Biomechanically Guided Prone-to-Supine Breast Image Registration

Prone-to-supine breast image registration has potential application in the fields of surgical and radiotherapy planning, image guided interventions, and multi-modal cancer diagnosis, staging, and therapy response prediction. However, breast image registration of three dimensional images acquired in different patient positions is a challenging problem, due to large deformations induced to the soft breast tissue caused by the change in gravity loading. We present a symmetric, biomechanical simulation based registration framework which aligns the images in a central, virtually unloaded configuration. The breast tissue is modelled as a neo-Hookean material and gravity is considered as the main source of deformation in the original images. In addition to gravity, our framework successively applies image derived forces directly into the unloading simulation in place of a subsequent image registration step. This results in a biomechanically constrained deformation. Using a finite difference scheme avoids an explicit meshing step and enables simulations to be performed directly in the image space. The explicit time integration scheme allows the motion at the interface between chest and breast to be constrained along the chest wall. The feasibility and accuracy of the approach presented here was assessed by measuring the target registration error (TRE) using a numerical phantom with known ground truth deformations, nine clinical prone MRI and supine CT image pairs, one clinical prone-supine CT image pair and four prone-supine MRI image pairs. The registration reduced the mean TRE for the numerical phantom experiment from initially 19.3 to 0.9 mm and the combined mean TRE for all fourteen clinical data sets from 69.7 to 5.6 mm

On the spreading of South Atlantic water into the northern Hemisphere

The upper branch of the meridional overturning circulation in the North Atlantic is fed by cross‐equatorial transport of various water masses from the Southern Hemisphere. Here, we study the large‐scale spreading of South Atlantic Water (SAW) into the western tropical North Atlantic from the equator to 25°N. The fractions of SAW in the upper ocean water masses are quantified using a water mass analysis applied on a data set of conductivity‐temperature‐depth data from the Hydrobase project and the Argo float program. To fill gaps in the data coverage and to gain insight into the mechanisms involved, the observations are complemented with results from the high‐resolution Family of Linked Atlantic Model Experiments model (equation image°), which has been shown to realistically simulate the inflow of SAW into the Caribbean. The analysis reveals the mean SAW propagation pathways in the North Atlantic and identifies the regions of largest variability. High SAW fractions in the thermocline and central water layers are limited to the region south of 10°N, where the water body consists of 80%–90% SAW. Thus, the zonal currents in the equatorial gyre are mainly formed of SAW. The weaker currents in the intermediate layer combined with a northward excursion of the North Equatorial Current allow the SAW in this layer to intrude farther north compared to the layers above. The transition into North Atlantic Water occurs gradually from 12°N to 20°N in the intermediate layer

Comparison of Image Registration Based Measures of Regional Lung Ventilation from Dynamic Spiral CT with Xe-CT

Purpose: Regional lung volume change as a function of lung inflation serves as an index of parenchymal and airway status as well as an index of regional ventilation and can be used to detect pathologic changes over time. In this article, we propose a new regional measure of lung mechanics --- the specific air volume change by corrected Jacobian. Methods: 4DCT and Xe-CT data sets from four adult sheep are used in this study. Nonlinear, 3D image registration is applied to register an image acquired near end inspiration to an image acquired near end expiration. Approximately 200 annotated anatomical points are used as landmarks to evaluate registration accuracy. Three different registration-based measures of regional lung mechanics are derived and compared: the specific air volume change calculated from the Jacobian (SAJ); the specific air volume change calculated by the corrected Jacobian (SACJ); and the specific air volume change by intensity change (SAI). Results: After registration, the mean registration error is on the order of 1 mm. For cubical ROIs in cubes with size 20 mm $\times$ 20 mm $\times$ 20 mm, the SAJ and SACJ measures show significantly higher correlation (linear regression, average $r^2=0.75$ and $r^2=0.82$) with the Xe-CT based measure of specific ventilation (sV) than the SAI measure. For ROIs in slabs along the ventral-dorsal vertical direction with size of 150 mm $\times$ 8 mm $\times$ 40 mm, the SAJ, SACJ, and SAI all show high correlation (linear regression, average $r^2=0.88$, $r^2=0.92$ and $r^2=0.87$) with the Xe-CT based sV without significant differences when comparing between the three methods. Conclusion: Given a deformation field by an image registration algorithm, significant differences between the SAJ, SACJ, and SAI measures were found at a regional level compared to the Xe-CT sV in four sheep that were studied

The use of activity-based approach as methodological basis of prospective social workers' training to sustainable development of social groups in Ukraine

The article shows the relevance of activity-based approach usage as methodological basis of prospective social workers' training to sustainable development of social groups. It is proved that future experts' training in this direction is important both for Ukraine and other countries. There have been revealed the types of activities (cognitive, creative, value-oriented, communicative), which provide the development of personality and social groups' subjectivity, their formation as the subjects of life and responsible social subjects that is essentail condition and indicator of their sustainable development. It has been emphasized that activity-based approach is the basis for the development of the technology of prospective social workers' training to sustainable development of social groups, which provides organization and management of this process as well as ensures gradual moving of prospective social workers to the level of self-management. There also has been substantiated necessity of the subjective and action approach usage (as important complement to activity one) which implementation ensures the development of subjective readiness of various social groups' representatives to individual and joint socially valuable actions that is essentail indicator of their sustainable development

Strings, branes and twistons: topological analysis of phase defects in excitable media such as the heart

Several excitable systems, such as the heart, self-organize into complex spatio-temporal patterns that involve wave collisions, wave breaks, and rotating vortices, of which the dynamics are incompletely understood. Recently, conduction block lines in two-dimensional media were recognized as phase defects, on which quasi-particles can be defined. These particles also form bound states, one of which corresponds to the classical phase singularity. Here, we relate the quasi-particles to the structure of the dynamical attractor in state space and extend the framework to three spatial dimensions. We reveal that 3D excitable media are governed by phase defect surfaces, i.e. branes, and three flavors of topologically preserved curves, i.e. strings: heads, tails, and pivot curves. We identify previously coined twistons as points of co-dimension three at the crossing of a head curve and a pivot curve. Our framework predicts splitting and branching phase defect surfaces that can connect multiple classical filaments, thereby proposing a new mechanism for the origin, perpetuation, and control of complex excitation patterns, including cardiac fibrillation

Analysis of cardiac arrhythmia sources using Feynman diagrams

The contraction of the heart muscle is triggered by self-organizing electrical patterns. Abnormalities in these patterns lead to cardiac arrhythmias, a prominent cause of mortality worldwide. The targeted treatment or prevention of arrhythmias requires a thorough understanding of the interacting wavelets, vortices and conduction block sites within the excitation pattern. Currently, there is no conceptual framework that covers the elementary processes during arrhythmogenesis in detail, in particular the transient pivoting patterns observed in patients, which can be interleaved with periods of less fragmented waves. Here, we provide such a framework in terms of quasiparticles and Feynman diagrams, which were originally developed in theoretical physics. We identified three different quasiparticles in excitation patterns: heads, tails and pivots. In simulations and experiments, we show that these basic building blocks can combine into at least four different bound states. By representing their interactions as Feynman diagrams, the creation and annihilation of rotor pairs are shown to be sequences of dynamical creation, annihilation and recombination of the identified quasiparticles. Our results provide a new theoretical foundation for a more detailed theory, analysis and mechanistic insights of topological transitions in excitation patterns, to be applied within and beyond the context of cardiac electrophysiology

Balancing branding and sales - The content strategist dilemma

This research strives to examine the impact of online brand communication on the content strategy of a premium brand in the context of ETON e-commerce store. The secondary purpose of the study provides the insight as to why brand message affects brand content strategy through various communication modes. The research set forth brand perspective to create an in-depth understanding of the mechanisms behind the content strategy and its importance for delivering the desired brand value to the target audience. The methodology of the study includes an overall approach to research analysis structure is based on the customer journey of ETON visitors. Finally a multimodal analysis of the brand color palette, typography and imagery has enabled an in-depth examination of editorial aspects of the brand content strategy. This study clarifies the strong connection between content strategy practices and effective brand message although complex mechanisms behind effective brand communication require a deeper focus on online branding. Branding, e-commerce platform and editorial content strategy practices have devised the key aspects of the successful performance of an online store. The research results have challenged the existing practices of content strategy approach and pointed to a strong contextual relevance for successful online brand communication tactics. Consequently, the study outcome points at a high risk of failed content delivery and ineffective brand message in the absence of data drive approach and in-depth understanding of consumer needs