We present here “Just Another Tool for Online Studies” (JATOS): an open source, cross-platform web application with a graphical user interface (GUI) that greatly simplifies setting up and communicating with a web server to host online studies that are written in JavaScript. JATOS is easy to install in all three major platforms (Microsoft Windows, Mac OS X, and Linux), and seamlessly pairs with a database for secure data storage. It can be installed on a server or locally, allowing researchers to try the application and feasibility of their studies within a browser environment, before engaging in setting up a server. All communication with the JATOS server takes place via a GUI (with no need to use a command line interface), making JATOS an especially accessible tool for researchers without a strong IT background. We describe JATOS’ main features and implementation and provide a detailed tutorial along with example studies to help interested researchers to set up their online studies. JATOS can be found under the Internet address: www.jatos.org.

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Word count: 4728Braunewell et al. Interactions of Visinin-like Proteins with Phospho-inositides 2The subcellular membrane localisation of neuronal calcium sensor (NCS) proteins in living cells, such as VILIP-1 and VILIP-3, differs substantially. We have followed the hypothesis that the differential localisation might be due to specific binding capabilities of individual VILIPs for phosphatidylinositol phosphates (PIPs). Several highly conserved lysine residues in the N-terminal region could provide favourable electrostatic interactions.Molecular modelling results support a binding site for phospho-inositides in the N-terminal area of VILIP-1, and the involvement of the conserved N-terminal lysine residues in binding the phosphoinositol head group. Experimentally, the binding of VILIP-1 to inositol derivatives was tested by a PIP strip assay, which showed the requirement of phosphorylation of the inositol group for the interaction of the protein with PIPs. Monolayer adsorption measurements showed a preference of VILIP-1 binding to PI(4,5)P 2 over PI(3,4,5)P 3 . The co-localisation of VILIP-1 with PI(4,5)P 2 at the cell surface membrane in hippocampal neurons further supports the idea of direct interactions of VILIP-1 with PIPs in living cells.

Kallikrein is involved in the generation of bradykinin during extracorporal circulation, that is believed to play an important role in cases of anaphylactic shock during hemodialysis. Therefore, a method for the assessment of kallikrein generation was developed, based on the chromogenic substrate S-2302. Comparison of kallikrein-like activity on glass using citrate or heparinized plasma demonstrated enhanced activity in the presence of heparin. The applicability of the assay, and the time course of kallikrein generation was demonstrated with glass and cuprophan. Membranes based on pure polyacrylonitrile, or its copolymers differing in their content of acrylic acid, 2-hydroxyethyl acrylate, and allylsulphonate were investigated with respect to kallikrein-like activity, and physicochemical surface properties. It was found that high content in 2-hydroxyethyl acrylate, and acrylic acid caused a substantial activation of the contact system while low content in allylsulphonate (less than 2 mol%) did not result in enhanced kallikrein-like activity. The activating materials were characterized to be highly wettable, and had the most negative zeta potentials.