The Research Data Centre of the Centre for European Economic Research (ZEW-FDZ)

Das Zentrum für Europäische Wirtschaftsforschung (ZEW) in Mannheim stellt eine Reihe seiner Forschungsdatensätze externen Wissenschaftlern zur Verfügung. Das ZEW folgt damit den Empfehlungen der „Kommission zur Verbesserung der informationellen Infrastruktur zwischen Wissenschaft und Statistik“ und unterstützt so die Weiterentwicklung der empirischen Wirtschafts- und Sozialforschung. Im November 2012 ist das ZEW-FDZ vom Rat für Sozial und Wirtschaftsdaten (RatSWD) akkreditiert worden. Bei den im ZEW-FDZ angebotenen ZEW Forschungsdaten handelt es sich um Mikrodaten von ZEW Unternehmensbefragungen, ZEW Expertenbefragungen oder ZEW Personenbefragungen. Die Daten einiger ZEW-Befragungen werden externen Wissenschaftlern in einer faktisch anonymisierten Form als Scientific-Use-Files zur Verfügung gestellt. Neben der Nutzung der Scientific-Use-Files können externe Forscher einen Antrag auf Nutzung von formal anonymisierten ZEW-Daten stellen, mit denen sie in den FDZ-Räumen des ZEW arbeiten dürfen. Formal anonymisiert bedeutet, dass die Datensätze weder Namen noch Adressen, aber ansonsten alle Originalangaben der Befragten enthalten. Die formal anonymisierten Daten befinden sich dazu auf einem Stand-alone-Rechner ohne Netzwerkanbindung, von dem keine Daten heruntergeladen werden können. Für das Mannheimer Innovationspanel (MIP) wurden zudem absolut anonymisierte Education-Use-Files für die Nutzung in der Lehre erstellt. Das ZEW-FDZ schließt an die bisherige Praxis des ZEW an, eigene Erhebungsdaten an externe Wissenschaftler weiterzugeben. Vor dem Start des ZEW-FDZ im Januar 2013, stellte das ZEW etwa 280 Wissenschaftlern vom ZEW erhobene Forschungsdaten zur Verfügung; die meisten sind Nutzer des Mannheimer Innovationspanels (250). Das ZEW wird sein Datenangebot für externe Wissenschaftler laufend erweitern. Dies gilt auch für Daten zukünftiger Erhebunge

Microbial light-activatable proton pumps as neuronal inhibitors to functionally dissect neuronal networks in C. elegans

Essentially any behavior in simple and complex animals depends on neuronal network function. Currently, the best-defined system to study neuronal circuits is the nematode Caenorhabditis elegans, as the connectivity of its 302 neurons is exactly known. Individual neurons can be activated by photostimulation of Channelrhodopsin-2 (ChR2) using blue light, allowing to directly probe the importance of a particular neuron for the respective behavioral output of the network under study. In analogy, other excitable cells can be inhibited by expressing Halorhodopsin from Natronomonas pharaonis (NpHR) and subsequent illumination with yellow light. However, inhibiting C. elegans neurons using NpHR is difficult. Recently, proton pumps from various sources were established as valuable alternative hyperpolarizers. Here we show that archaerhodopsin-3 (Arch) from Halorubrum sodomense and a proton pump from the fungus Leptosphaeria maculans (Mac) can be utilized to effectively inhibit excitable cells in C. elegans. Arch is the most powerful hyperpolarizer when illuminated with yellow or green light while the action spectrum of Mac is more blue-shifted, as analyzed by light-evoked behaviors and electrophysiology. This allows these tools to be combined in various ways with ChR2 to analyze different subsets of neurons within a circuit. We exemplify this by means of the polymodal aversive sensory ASH neurons, and the downstream command interneurons to which ASH neurons signal to trigger a reversal followed by a directional turn. Photostimulating ASH and subsequently inhibiting command interneurons using two-color illumination of different body segments, allows investigating temporal aspects of signaling downstream of ASH

Beyond Control-Flow: Extending Business Process Configuration to Roles and Objects

A configurable process model is an integrated representation of multiple variants of a business process. It is designed to be individualized to meet a particular set of requirements. As such, configurable process models promote systematic reuse of proven or common practices. Existing notations for configurable process modeling focus on capturing tasks and control-flow dependencies, neglecting equally important aspects of business processes such as data flow, material flow and resource management. This paper fills this gap by proposing an integrated meta-model for configurable processes with advanced features for capturing resources involved in the performance of tasks (through task-role associations) as well as flow of data and physical artifacts (through task-object associations). Although embodied as an extension of a popular process modeling notation, namely EPC, the meta-model is defined in an abstract and formal manner to make it applicable to other notations

Territorial Tactics: The Socio-spatial Significance of Private Policing Strategies in Cape Town

This paper analyses the policing strategies of private security companies operating in urban space. An existing literature has considered the variety of ways that territory becomes of fundamental importance in the work of public police forces. However, this paper examines territory in the context of private security companies. Drawing on empirical research in Cape Town, it examines how demarcated territories become key subjects in private policing. Private security companies are responsible for a relatively small section of the city, while in contrast the public police ultimately have to see city space as a whole. Hence, private policing strategy becomes one of displacement, especially of so-called undesirables yielding a patchworked public space associated with private enclaves of consumption. The conclusions signal the historical resonances and comparative implications of these political-legal-security dynamics. © 2013 Urban Studies Journal Limited

Symmetric and asymmetric action integration during cooperative object manipulation in virtual environments

Cooperation between multiple users in a virtual environment (VE) can take place at one of three levels. These are defined as where users can perceive each other (Level 1), individually change the scene (Level 2), or simultaneously act on and manipulate the same object (Level 3). Despite representing the highest level of cooperation, multi-user object manipulation has rarely been studied. This paper describes a behavioral experiment in which the piano movers' problem (maneuvering a large object through a restricted space) was used to investigate object manipulation by pairs of participants in a VE. Participants' interactions with the object were integrated together either symmetrically or asymmetrically. The former only allowed the common component of participants' actions to take place, but the latter used the mean. Symmetric action integration was superior for sections of the task when both participants had to perform similar actions, but if participants had to move in different ways (e.g., one maneuvering themselves through a narrow opening while the other traveled down a wide corridor) then asymmetric integration was superior. With both forms of integration, the extent to which participants coordinated their actions was poor and this led to a substantial cooperation overhead (the reduction in performance caused by having to cooperate with another person)