Development of "Boni-Protect" - a yeast preparation for use in the control of postharvest diseases of apples

Postharvest pathogens cause major losses in apple production. Gloeosporium album (Pezicula alba) and Gloeosporium perennans (Pezicula malicorticis) are the main pathogens in organic fruit growing. There are several microorganisms with an antagonistic efficency against these fungi. Out of these organisms two yeast isolates have been chosen to develop the plant strengthener Boni-Protect. Boni-Protect reduced the symp-tom development of P. malicorticis, B. cinerea and P. expansum after artificial inoculation of apple wounds. In several field trials preharvest applications of Boni-Protect led to reduced disease development during stor-age

Quantum-coherent phase oscillations in synchronization

Recently, several studies have investigated synchronization in quantum-mechanical limit-cycle oscillators. However, the quantum nature of these systems remained partially hidden, since the dynamics of the oscillator's phase was overdamped and therefore incoherent. We show that there exist regimes of underdamped and even quantum-coherent phase motion, opening up new possibilities to study quantum synchronization dynamics. To this end, we investigate the Van der Pol oscillator (a paradigm for a self-oscillating system) synchronized to an external drive. We derive an effective quantum model which fully describes the regime of underdamped phase motion and additionally allows us to identify the quality of quantum coherence. Finally, we identify quantum limit cycles of the phase itself.Comment: 6 pages + Supplemental Materia

Privacy Threat Model for Data Portability in Social Network Applications

The advent of the participatory Web and social network applications has changed our communication behavior and the way we express ourselves on the Web. Social network application providers benefit from the increasing amount of personally identifiable information willingly displayed on their sites but, at the same time, risks of data misuse threaten the information privacy of individual users as well as the providers’ business model. From recent research, this paper reports the major requirements for developing privacy-preserving social network applications and proposes a privacy threat model that can be used to enhance the information privacy in data or social network portability initiatives by determining the issues at stake related to the processing of personally identifiable information

General linearized theory of quantum fluctuations around arbitrary limit cycles

The theory of Gaussian quantum fluctuations around classical steady states in nonlinear quantum-optical systems (also known as standard linearization) is a cornerstone for the analysis of such systems. Its simplicity, together with its accuracy far from critical points or situations where the nonlinearity reaches the strong coupling regime, has turned it into a widespread technique, which is the first method of choice in most works on the subject. However, such a technique finds strong practical and conceptual complications when one tries to apply it to situations in which the classical long-time solution is time dependent, a most prominent example being spontaneous limit-cycle formation. Here we introduce a linearization scheme adapted to such situations, using the driven Van der Pol oscillator as a testbed for the method, which allows us to compare it with full numerical simulations. On a conceptual level, the scheme relies on the connection between the emergence of limit cycles and the spontaneous breaking of the symmetry under temporal translations. On the practical side, the method keeps the simplicity and linear scaling with the size of the problem (number of modes) characteristic of standard linearization, making it applicable to large (many-body) systems.Comment: Constructive suggestions and criticism are welcom

Context-Aware Adaptation of Mobile Multimedia Presentations

With increasing capabilities of mobile devices, the number of mobile multimedia services grows steadily. Usage of multimedia services and especially the presentation of multimedia content is more challenging in a mobile environment than on stationary devices due to the diversity of mobile devices and their parameters, the sparse resources of the air interface or the changing context. This position paper introduces an approach for context-aware adaptation of mobile multimedia presentations. For this, a middleware architecture is proposed that performs an automatic and distributed adaptation process: while the server provides a pre-processing of the content, the client completes the overall adaptation. To support this task, the Adaptation Rule Language (ARL) was developed which is introduced in this paper as well

On the spin--boson model with a sub--Ohmic bath

We study the spin--boson model with a sub--Ohmic bath using infinitesimal unitary transformations. Contrary to some results reported in the literature we find a zero temperature transition from an untrapped state for small coupling to a trapped state for strong coupling. We obtain an explicit expression for the renormalized level spacing as a function of the bare papameters of the system. Furthermore we show that typical dynamical equilibrium correlation functions exhibit an algebaric decay at zero temperature.Comment: 9 pages, 2 Postscript figure