Bounded time computation on metric spaces and Banach spaces

We extend the framework by Kawamura and Cook for investigating computational complexity for operators occurring in analysis. This model is based on second-order complexity theory for functions on the Baire space, which is lifted to metric spaces by means of representations. Time is measured in terms of the length of the input encodings and the required output precision. We propose the notions of a complete representation and of a regular representation. We show that complete representations ensure that any computable function has a time bound. Regular representations generalize Kawamura and Cook's more restrictive notion of a second-order representation, while still guaranteeing fast computability of the length of the encodings. Applying these notions, we investigate the relationship between purely metric properties of a metric space and the existence of a representation such that the metric is computable within bounded time. We show that a bound on the running time of the metric can be straightforwardly translated into size bounds of compact subsets of the metric space. Conversely, for compact spaces and for Banach spaces we construct a family of admissible, complete, regular representations that allow for fast computation of the metric and provide short encodings. Here it is necessary to trade the time bound off against the length of encodings

A New Measure of Equity Duration: The Duration-Based Explanation of the Value Premium Revisited

This paper uses analysts' forecasts to estimate a share's equity duration, a measure of a company's average cash-flow maturity. We find that short duration equity is associated with high expected and realized returns, which cannot be attributed to the shares' systematic risk exposure as implied by the market beta. Instead, we show that equity duration is a priced risk factor with similar properties as the Fama-French value factor B/M ratio. Our analysis suggests that the value premium might be a compensation for the value firms' higher exposure to cash-flow risk

Qualitative Analysen zur harmonisierten Berechnung einer Alterungsrückstellung und der verfassungskonformen Ausgestaltung ihrer Portabilität: Endbericht - Studie im Auftrag des Verbraucherzentrale Bundesverband (vzbv) e.V.

Die Studie prüft insbesondere anhand einschlägiger in der Literatur entwickelter Modelle die Frage, ob eine Verbesserung der Wechseloptionen für in der Privaten Krankenversicherung (PKV) vollversicherte Personen möglich ist und wie sie ggfs. ausgestaltet sein sollte. Eine Entwicklung eines eigenständigen Modelles oder eine konkrete medizinisch-ökonomische Operationalisierung vorliegender allgemeinerer Konzeptionen ist nicht Gegenstand der Expertise

The extracellular EXO protein mediates cell expansion in Arabidopsis leaves

<p>Abstract</p> <p>Background</p> <p>The <it>EXO </it>(<it>EXORDIUM</it>) gene was identified as a potential mediator of brassinosteroid (BR)-promoted growth. It is part of a gene family with eight members in Arabidopsis. <it>EXO </it>gene expression is under control of BR, and <it>EXO </it>overexpression promotes shoot and root growth. In this study, the consequences of loss of <it>EXO </it>function are described.</p> <p>Results</p> <p>The <it>exo </it>loss of function mutant showed diminished leaf and root growth and reduced biomass production. Light and scanning electron microscopy analyses revealed that impaired leaf growth is due to reduced cell expansion. Epidermis, palisade, and spongy parenchyma cells were smaller in comparison to the wild-type. The <it>exo </it>mutant showed reduced brassinolide-induced cotyledon and hypocotyl growth. In contrast, <it>exo </it>roots were significantly more sensitive to the inhibitory effect of synthetic brassinolide. Apart from reduced growth, <it>exo </it>did not show severe morphological abnormalities. Gene expression analyses of leaf material identified genes that showed robust EXO-dependent expression. Growth-related genes such as <it>WAK1</it>, <it>EXP5</it>, and <it>KCS1</it>, and genes involved in primary and secondary metabolism showed weaker expression in <it>exo </it>than in wild-type plants. However, the vast majority of BR-regulated genes were normally expressed in <it>exo</it>. HA- and GFP-tagged EXO proteins were targeted to the apoplast.</p> <p>Conclusion</p> <p>The <it>EXO </it>gene is essential for cell expansion in leaves. Gene expression patterns and growth assays suggest that EXO mediates BR-induced leaf growth. However, EXO does not control BR-levels or BR-sensitivity in the shoot. EXO presumably is involved in a signalling process which coordinates BR-responses with environmental or developmental signals. The hypersensitivity of <it>exo </it>roots to BR suggests that EXO plays a diverse role in the control of BR responses in the root.</p

The extracellular EXO protein mediates cell expansion in Arabidopsis leaves

<p>Abstract</p> <p>Background</p> <p>The <it>EXO </it>(<it>EXORDIUM</it>) gene was identified as a potential mediator of brassinosteroid (BR)-promoted growth. It is part of a gene family with eight members in Arabidopsis. <it>EXO </it>gene expression is under control of BR, and <it>EXO </it>overexpression promotes shoot and root growth. In this study, the consequences of loss of <it>EXO </it>function are described.</p> <p>Results</p> <p>The <it>exo </it>loss of function mutant showed diminished leaf and root growth and reduced biomass production. Light and scanning electron microscopy analyses revealed that impaired leaf growth is due to reduced cell expansion. Epidermis, palisade, and spongy parenchyma cells were smaller in comparison to the wild-type. The <it>exo </it>mutant showed reduced brassinolide-induced cotyledon and hypocotyl growth. In contrast, <it>exo </it>roots were significantly more sensitive to the inhibitory effect of synthetic brassinolide. Apart from reduced growth, <it>exo </it>did not show severe morphological abnormalities. Gene expression analyses of leaf material identified genes that showed robust EXO-dependent expression. Growth-related genes such as <it>WAK1</it>, <it>EXP5</it>, and <it>KCS1</it>, and genes involved in primary and secondary metabolism showed weaker expression in <it>exo </it>than in wild-type plants. However, the vast majority of BR-regulated genes were normally expressed in <it>exo</it>. HA- and GFP-tagged EXO proteins were targeted to the apoplast.</p> <p>Conclusion</p> <p>The <it>EXO </it>gene is essential for cell expansion in leaves. Gene expression patterns and growth assays suggest that EXO mediates BR-induced leaf growth. However, EXO does not control BR-levels or BR-sensitivity in the shoot. EXO presumably is involved in a signalling process which coordinates BR-responses with environmental or developmental signals. The hypersensitivity of <it>exo </it>roots to BR suggests that EXO plays a diverse role in the control of BR responses in the root.</p