Abstract The loss of inter‐neuron communication is related to many neuronal diseases such as Alzheimer's dementia. The nicotinic acetylcholine receptor (nAChR) plays a crucial role in this process and is severely affected upon disease progression. Successful therapy approaches rely on modulation of response signals, initiated by the flux of ions through the receptor integrated ion channel at the post‐synaptic membrane. We present here the comparison of two methods for calculating the energy barrier of nAChR mediated ion permeation, in terms of accuracy and performance. Detailed descriptions of archetypical Gromacs characteristics are given offering better insight into computational service providers to meet the needs of scientists. Copyright © 2010 John Wiley & Sons, Ltd.

Software as a Service (SaaS) providers enable the on-demand use of software, which is an intriguing concept for business and scientific applications. Typically, service level agreements (SLAs) are specified between the provider and the user, defining the required quality of service (QoS). Today SLA aware solutions only exist for business applications. We present a general SaaS architecture for scientific software that offers an easy-to-use web interface. Scientists define their problem description, the QoS requirements and can access the results through this portal. Our algorithms autonomously test the feasibility of the SLA and, if accepted, guarantee its fulfillment. This approach is independent of the underlying cloud infrastructure and successfully deals with performance fluctuations of cloud instances. Experiments are done with a scientific application in private and public clouds and we also present the implementation of a high-performance computing (HPC) cloud dedicated for scientific applications.

No abstract available.