Continuous time limit of repeated quantum observations

[no abstract

Essays in finance: The impact of trust, firm efficiency, investor relations, and operational leanness on financial markets

This dissertation consists of four essays and aims to contribute to a better understanding of financial markets and investor behavior. The first three essays focus on the effects of the COVID-19 crisis, which constituted an exogenous shock to a firm’s future cash flows and thus led to market collapse. Given the dramatic downturn, the COVID-19 crisis presents an opportunity to examine how market participants evaluate the importance of certain firm characteristics for the firm’s ability to generate future cash flows and also how characteristics of countries and societies influence capital market outcomes. In Essay 1, we therefore provide evidence that societal trust and trust in the country’s government significantly reduced stock market volatility in reaction to COVID-19 case announcements during the crisis period. We relate this result to trust alleviating uncertainty among investors about the country’s ability to overcome the crisis. In Essay 2, we show firms which use their resources more efficiently to experience higher returns during the crisis. We argue that the outperformance of efficient firms relates to these firms having less risky expected cash flows and thus a lower risk of default, which is consistent with the view in Frijns et al. (2012). In Essay 3, we study whether having better-quality investor relations (IR) helps to alleviate information frictions among market participants and is thus valuable for firms. The results suggest that firms with better-quality IR experienced higher returns, retained more incumbent institutional investors, and also attracted more new institutional investors during the crisis period. Finally, Essay 5 moves away from the topic of the COVID-19 crisis, but it also contributes to a better understanding of financial markets and investor behavior. In this last essay, we examine whether institutional investors view operational leanness as a competitive advantage resulting in higher expected cash flows. The results provide evidence that institutional investors generally appear to prefer lean firms since the reduction in operational slack is associated with a cost advantage. However, the results also suggest that institution types differ substantially in how they evaluate operational leanness because of market and information frictions

Microtubule stabilization specifies initial neuronal polarization

Axon formation is the initial step in establishing neuronal polarity. We examine here the role of microtubule dynamics in neuronal polarization using hippocampal neurons in culture. We see increased microtubule stability along the shaft in a single neurite before axon formation and in the axon of morphologically polarized cells. Loss of polarity or formation of multiple axons after manipulation of neuronal polarity regulators, synapses of amphids defective (SAD) kinases, and glycogen synthase kinase-3β correlates with characteristic changes in microtubule turnover. Consistently, changing the microtubule dynamics is sufficient to alter neuronal polarization. Application of low doses of the microtubule-destabilizing drug nocodazole selectively reduces the formation of future dendrites. Conversely, low doses of the microtubule-stabilizing drug taxol shift polymerizing microtubules from neurite shafts to process tips and lead to the formation of multiple axons. Finally, local stabilization of microtubules using a photoactivatable analogue of taxol induces axon formation from the activated area. Thus, local microtubule stabilization in one neurite is a physiological signal specifying neuronal polarization

Feinwanderung an elektrischen Kohle-Kohlekontakten

On carbon-carbon contacts operated with d.c. the author has observed carbon transfer in normal direction i.e. from the anode to the cathode, if the contact load does not exceed a certain value. This is the same direction as the well known "bridge transfer" in metal-metal contacts, although a liquid bridge cannot be formed in the gap of carbon-carbon contacts. This phenomenon is explained by the local heating of the anode, effected by electrons emitted from the cathode through the gap. Thus the anode is vapourized and carbon vapour condensed on the colder cathode. Anomalous transfer i.e. from the cathode to the anode may result, if the cathode is subjected to additional heat

Fast fashion: supply-chain management as the basis for disruptive business model innovation - a case study in the context of the theory of the firm

Supply Chain Management has been traditionally understood as the management and optimisation of logistic processes regarding the management of flows of goods. Business research recognises the Supply Chain as mainly a support service for its key activities, and which is generally examined in regard to the technical and engineering aspects with the sole objective of finding the minimum cost solution. This research argues instead that, in the fashion industry at least, Supply Chain Management becomes a key activity in Value Chain management and therefore in the business model. As a consequence, this study is not a Supply Chain Management Study in the traditional sense but rather examines the disruptive fashion business model focusing on innovation, starting with the restructuring of the Supply Chain, based on information technology revolutionising the retail business and, particularly, the fashion industry. Information technology has generated a completely new Supply Chain Management model, leading to disruptive competitive advantage. This research focuses on the exploration of the Supply Chain at the level of the theory of the firm and the concept of the business model, rather than at a technical or operational level. The theoretical lens is at firm level examining the concept of the business model. The empirical part of this study applies qualitative and quantitative methods, as indicated. The main quantitative method is financial analysis, which enables the examination of fifteen industry-leading companies within the fashion industry. Additionally, descriptive and bivariate statistical analysis are applied to examine the statistical strength and significance of relationships between Supply Chain and business performance variables. The second part of the empirical research uses expert interviews with industry professionals to verify or falsify the findings of the statistical analysis, and to develop the findings further. The classical Supply Chain research approach is also questionable and should be revisited; typical Supply Chain research variables include efficiency, effectiveness, cycle time, postponement, whereas the main objective of Supply Chain research is the optimum configuration and design of a Supply Chain. This research study makes a unique contribution to knowledge situating the supply chain within the context of the theory of the firm and provides evidence that the Supply Chain is more than a support function, it represents a key business activity to increase competitiveness providing the infrastructure for disruptive business model innovations. The overall result of the industry case study and the expert interviews is that digitalisation changes the possibilities in the Supply Chain configuration considerably. New Supply Chain configurations enabled by digitalisation have led to disruptive business model innovations, so that Supply Chain Management has become a key business activity because it is the basis of the reorganising of the relationship between the firm’s purchase markets, product development, manufacturing, distribution channels, and the consumer market. This development represents a restricted change at a lower level of business operations but a major one at the strategic level, with implications for the theory of the firm and the theory of a firm’s growth. In this regard, the main issues of future Supply Chain research may therefore be the challenges of delivering the right goods at the right time to the right location and how to deliver the right data regarding commodity flows to the right decision maker, within the right time. The Supply Chain department may gradually become a Value Chain Management department, the business model development department, at least in the industrial firm. However, the term management may be somewhat misleading in this context because management means controlling, implementing and supervising network-centric operations in which defined production processes, reporting, distribution processes and decisions almost always initiated by real-time POS data leading to a highly responsive value chain

Stepwise pathway for early evolutionary assembly of dissimilatory sulfite and sulfate reduction

Funding Information: FLS and SN acknowledge support from the Wiener Wissenschafts, Forschungs- und Technologiefonds (Austria) through the grant VRG15-007. FLS gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation program (grant agreement 803768). IACP acknowledges support from Fundação para a Ciência e Tecnologia (Portugal) through grants PTDC/BIA-MIC/6512/2014 and PTDC/BIA-BQM/29118/2017, R&D unit MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020), and LS4FUTURE Associated Laboratory (LA/P/0087/2020). The computational results of this work have been achieved using the Life Science Compute Cluster (LiSC) of the University of Vienna. Funding Information: FLS and SN acknowledge support from the Wiener Wissenschafts, Forschungs- und Technologiefonds (Austria) through the grant VRG15-007. FLS gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation program (grant agreement 803768). IACP acknowledges support from Fundação para a Ciência e Tecnologia (Portugal) through grants PTDC/BIA-MIC/6512/2014 and PTDC/BIA-BQM/29118/2017, R&D unit MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020), and LS4FUTURE Associated Laboratory (LA/P/0087/2020). The computational results of this work have been achieved using the Life Science Compute Cluster (LiSC) of the University of Vienna. Publisher Copyright: © 2023, The Author(s).Microbial dissimilatory sulfur metabolism utilizing dissimilatory sulfite reductases (Dsr) influenced the biochemical sulfur cycle during Earth’s history and the Dsr pathway is thought to be an ancient metabolic process. Here we performed comparative genomics, phylogenetic, and synteny analyses of several Dsr proteins involved in or associated with the Dsr pathway across over 195,000 prokaryotic metagenomes. The results point to an archaeal origin of the minimal DsrABCMK(N) protein set, having as primordial function sulfite reduction. The acquisition of additional Dsr proteins (DsrJOPT) increased the Dsr pathway complexity. Archaeoglobus would originally possess the archaeal-type Dsr pathway and the archaeal DsrAB proteins were replaced with the bacterial reductive-type version, possibly at the same time as the acquisition of the QmoABC and DsrD proteins. Further inventions of two Qmo complex types, which are more spread than previously thought, allowed microorganisms to use sulfate as electron acceptor. The ability to use the Dsr pathway for sulfur oxidation evolved at least twice, with Chlorobi and Proteobacteria being extant descendants of these two independent adaptations.publishersversioninpres

Hibridación natural en mariposas heliconinas: el límite de las especies como un continuo

Background To understand speciation and the maintenance of taxa as separate entities, we need information about natural hybridization and gene flow among species. Results Interspecific hybrids occur regularly in Heliconius and Eueides (Lepidoptera: Nymphalidae) in the wild: 26–29% of the species of Heliconiina are involved, depending on species concept employed. Hybridization is, however, rare on a per-individual basis. For one well-studied case of species hybridizing in parapatric contact (Heliconius erato and H. himera), phenotypically detectable hybrids form around 10% of the population, but for species in sympatry hybrids usually form less than 0.05% of individuals. There is a roughly exponential decline with genetic distance in the numbers of natural hybrids in collections, both between and within species, suggesting a simple 'exponential failure law' of compatibility as found in some prokaryotes. Conclusion Hybridization between species of Heliconius appears to be a natural phenomenon; there is no evidence that it has been enhanced by recent human habitat disturbance. In some well-studied cases, backcrossing occurs in the field and fertile backcrosses have been verified in insectaries, which indicates that introgression is likely, and recent molecular work shows that alleles at some but not all loci are exchanged between pairs of sympatric, hybridizing species. Molecular clock dating suggests that gene exchange may continue for more than 3 million years after speciation. In addition, one species, H. heurippa, appears to have formed as a result of hybrid speciation. Introgression may often contribute to adaptive evolution as well as sometimes to speciation itself, via hybrid speciation. Geographic races and species that coexist in sympatry therefore form part of a continuum in terms of hybridization rates or probability of gene flow. This finding concurs with the view that processes leading to speciation are continuous, rather than sudden, and that they are the same as those operating within species, rather than requiring special punctuated effects or complete allopatry. Although not qualitatively distinct from geographic races, nor 'real' in terms of phylogenetic species concepts or the biological species concept, hybridizing species of Heliconius are stably distinct in sympatry, and remain useful groups for predicting morphological, ecological, behavioural and genetic characteristics

Quantensprung oder Störenfried?

Die Windkraftnutzung drängt aufs Meer. Doch die tatsächlichen Wirkungen von Windparks auf die Meeresumwelt sind noch weitgehend unbekannt. Ökologische Forschung und die Raumordnung werden damit zum Schlüssel für den naturverträglichen Ausbau der Offshore-Windkraftnutzung

Facilitating collaboration in high-performance computing projects with an interaction room

The design, development and deployment of scientific computing applications can be quite complex as they require scientific, High-Performance Computing (HPC), and software engineering expertise. Often, HPC applications are however developed by end users who are experts in their scientific domain, but need support from a supercomputing centre for the engineering and optimization aspects. The cooperation and communication between experts from these quite different disciplines can be difficult though. We therefore propose to employ the Interaction Room, a technique that facilitates interdisciplinary collaboration in complex software projects.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Grant Agreement No. 754304 DEEP-EST.Peer Reviewed Camera Read