A remarkable feature at Mnajdra

During a visit of the Southern Temple (Lower Temple) at Mnajdra in April 2007 a remarkable feature was observed. After studying recent and older literature on the Mnajdra temples, it seemed to me as though nobody had previously discovered or, at least, recorded it. In April 2008 I was informed about a single written reference. Another well-hidden reference came to light in April 2010. Both will be presented in this article.peer-reviewe

A Contribution to Functional Data Analysis

Functional Principal Component Analysis (FPCA) approximates a sample curve as a linear combination of orthogonal basis functions. It is often possible to describe the essential parts of the variations of functional data by looking only at a usually very small set of principal components and the corresponding principal scores. Two approaches based on FPCA to estimate smooth derivatives of noisy and discretely observed high-dimensional spatial curves are presented. To handle observed data, both approaches rely on local polynomial regressions. The requirements under which the methods are asymptotically equivalent are evaluated. If the curves are contained in a finite-dimensional function space, it is shown that both methods providing better rates of convergence than estimating the curves individually. The methodology is illustrated in a simulation and empirical study, in which state price density (SPD) surfaces from call option prices are estimated. Serious issues deriving to an FPCA decomposition arise in presence of a Registration problem. Registration aims to decompose amplitude and phase variation of samples of curves. Phase variation is captured by warping functions which monotonically transform the domains. Resulting registered curves should then only exhibit amplitude variation. Most existing registration method rely on aligning typical shape features like peaks or valleys to be found in each sample function. It is shown that this is not necessarily an optimal strategy for subsequent statistical data exploration and inference. In this context a major goal is to identify low dimensional linear subspaces of functions that are able to provide accurate approximations of the observed functional data. Problems of identifiability are discussed in detail, and connections to established registration procedures are analyzed. The methodology is applied to simulated and real data for example an analysis of the juggling dataset. Here an elementary landmark registration is used to extract the juggling cycles from the data. The resulting cycles are then registered to functional principal components. After the registration step the focus is then at the functional principal component analysis to explain the amplitude variation of the cycles. More results about the behavior of the juggler's movements of the hand during the juggling trials are obtained by a further investigation of the principal scores

LIGHTest: Lightweight Infrastrucutre for Global and Heterogeneous Trust Management

The EU-funded LIGHTest project is developing a global trust infrastructure that enables an easy and efficient verification process of electronic transactions, even if the involved instances belong to different trust domains. LIGHTest builds on the available internet Domain Name System (DNS) infrastructure. This paper gives an overview on the LIGHTest project, its reference architecture and variety of application fields

A system of inverted nonsmooth pendula: modelling an elderly person stepping over an obstacle

We derive a mechanical model of human motion where an elderly person decides to step over an obstacle rather than avoiding it. Such a decision may be deliberate or forced due to a sudden appearing obstacle in his/her way. The model is represented by a nonautonomous system of ordinary differential equations with discontinuous right hand side. We provide a notion of lateral stability. It is shown that increasing the angle between legs increases stability linearly. This implies that an individual reduces the risk of falling due to stepping over an obstacle by increasing the angle between legs

Do parties perceive their voter potentials correctly? Reconsidering the spatial logic of electoral competition

Political parties strive for maximizing their vote shares. One way to achieve this goal is to attract voters from competitors. A precondition for strategies aiming at attracting these voters is that parties perceive their voter potentials among their rivals' electorates correctly. Yet, hardly anything is known about such perceptions. To fill this gap, we develop analogue measures of a party's perceived and its actual voter potential for each competitor in a party system. Combining elite and mass surveys conducted in Germany, we show that perceived and actual voter potentials depend on spatial considerations but also that not all parties are able to correctly evaluate their potentials. These deviations can be traced back to differences in the perceived placement of political actors between elites and citizens. This supports the spatial logic of party competition but it also points to potential pitfalls for strategic behavior of political parties

Vergleichende Untersuchungen der Membrantoxizität und der Zytotoxizität von zahnärztlichen Füllungswerkstoffen unter Anwendung des [3H]Arachidonsäure-Freisetzungstests und des XTT-Reduktionstests EZ4U

Die Prüfung zahnärztlicher Werkstoffe auf Biokompatibilität ist eine notwendige und zwingende Voraussetzung vor Einführung eines Materials in die Zahnheilkunde. In Anbetracht der zunehmenden Anzahl von auf dem Markt befindlichen Produkten, fällt es dem anwendenden Zahnarzt zunehmend schwerer, eine für Patient und Behandler sichere und sinnvolle Auswahl der zahnärztlichen Materialien zu treffen. Hinzu kommt, dass die Vielzahl der möglichen Prüfmethoden dem Anwender die Auswahl eines für Arzt und Patienten geeigneten Produktes erheblich erschwert. Deshalb ist es dringend erforderlich, in Ergänzung zu den bestehenden Normen (Council Directive 93/42/EEC, ISO 10993, ISO 7405, ISO 14971, ISO 14155-1), einen einheitlichen Bewertungsmaßstab inklusive der definierten Beschreibung der Prüfmethoden für die Beurteilung der Biokompatibilität von Dentalprodukten einzuführen. Die Biokompatibilität eines Werkstoffes insgesamt kann jedoch nicht mit einem einzelnen Test, sondern nur auf der Grundlage der Ergebnisse einer Gruppe von Testverfahren beurteilt werden. Die vorliegenden Ergebnisse sind ein weiterer Beleg für die zum Teil gravierenden Unterschiede in der Zellverträglichkeit von Dentalwerkstoffen. Die Entwicklung von Dentalwerkstoffen bis zum fertigen Medizinprodukt sollte daher von einer sorgfältigen biologischen Prüfung sowohl der Ausgangsmaterialien als auch der Endprodukte durch geeignete voneinander unabhängig durchgeführte Testverfahren begleitet sein

The changing meaning of left and right: supply- and demand-side effects on the perception of party positions

Political conflict is often described in terms of "left" and "right" even though societal conflicts stem from various sub-dimensions such as economic and cultural issues. We argue that individuals map parties’ left-right positions based on party positions on such underlying dimensions, though their impact depends on their importance for parties and citizens. To test this, we study the German Alternative für Deutschland (AfD) whose programmatic appeal has changed fundamentally in the last years, as have citizens’ issue concerns. Using longitudinal data from the German Longitudinal Election Study (GLES), we find that citizens' perceptions of the AfD's left-right position are more closely related to the party's position on specific issues (1) when these issues are prominent in the party's communication and (2) for citizens that care more about these issues. Moreover, how voters perceive left and right in comparison to parties' issue emphasis also affects vote choice. Our findings have important implications for the meaning of left and right, electoral behaviour, representation, and party competition

The Catalyzing Role of FinTechs for Innovation Sourcing in Financial Services

In recent years a lively scene of startup companies developed focusing specifically on the financial services sector. These so-called FinTechs are characterized by highlyinnovative capacities, rapid development methods and a short time to market for their services and technical solutions. This external source of innovation can pose a competitive threat to traditional financial service companies or, on the contrary, may add value by serving as an additional resource for new ideas and technical solutions. Using a multiple case study approach, 18 interviews were conducted with representatives of FinTechs, financial services corporations, and specialized consulting firms. Westudy how large corporations and FinTechs interact with each other, what organizational setups were chosen and how knowledge transfer is organized for successful collaboration.Our results indicate that the organizational setup, split into three dimensions, has a strong impact on the integration of external knowledge which, in turn, affectsthe success of innovation sourcing

From the European debt crisis to a culture of closed borders: how issue salience changes the meaning of left and right for perceptions of the German AfD party

Political parties are traditionally described as being on a left-right spectrum according to their economic policies. However, socio-cultural dynamics also contribute to the public perception of parties. Looking at the case of Alternative für Deutschland, Heiko Giebler, Thomas M. Meyer and Markus Wagner show how shifting issue salience from one to the other both by the party and voters affects how the party is perceived in terms of left and right

Effects of prolonged darkness and temperature on the lipid metabolism in the benthic diatom Navicula perminuta from the Arctic Adventfjorden, Svalbard

The Arctic represents an extreme habitat for phototrophic algae due to long periods of darkness caused by the polar night (~4 months darkness). Benthic diatoms, which dominate microphytobenthic communities in shallow water regions, can survive this dark period, but the underlying physiological and biochemical mechanisms are not well understood. One of the potential mechanisms for long-term dark survival is the utilisation of stored energy products in combination with a reduced basic metabolism. In recent years, water temperatures in the Arctic increased due to an ongoing global warming. Higher temperatures could enhance the cellular energy requirements for the maintenance metabolism during darkness and, therefore, accelerate the consumption of lipid reserves. In this study, we investigated the macromolecular ratios and the lipid content and composition of Navicula cf. perminuta Grunow, an Arctic benthic diatom isolated from the microphytobenthos of Adventfjorden (Svalbard, Norway), over a dark period of 8 weeks at two different temperatures (0 and 7 °C). The results demonstrate that N. perminuta uses the stored lipid compound triacylglycerol (TAG) during prolonged dark periods, but also the pool of free fatty acids (FFA). Under the enhanced temperature of 7 °C, the lipid resources were used significantly faster than at 0 °C, which could consequently lead to a depletion of this energy reserves before the end of the polar night. On the other hand, the membrane building phospho- and glycolipids remained unchanged during the 8 weeks darkness, indicating still intact thylakoid membranes. These results explain the shorter survival times of polar diatoms with increasing water temperatures during prolonged dark periods