GridLabs: Facilitating collaborative access to remote laboratories

eScience is usually characterized by the cooperation of distributed groups of researchers who share data and computing environments and perform experiments together. Often immense data sets that were produced by expensive equipments need to be accessed and evaluated. Such eScience scenarios require both, support for collaboration of researchers at distant locations and also the remote control of the shared laboratory devices. However, this type of remote experimentation and collaboration must be taught during university education. In this paper, we propose a framework that supports the training of above practices through the provision of a dedicated collaboration environment. It extends current approaches with support for a life cycle of remote labs, including scheduling the access to remote labs as well as defining access permissions. Our experiences in teaching lab courses suggest that the approach is also applicable in eScience scenarios

Predominance of Biotic over Abiotic Formation of Halogenated Hydrocarbons in Hypersaline Sediments in Western Australia

Volatile halogenated organic compounds (VOX) contribute to ozone depletion and global warming. There is evidence of natural VOX formation in many environments ranging from forest soils to salt lakes. Laboratory studies have suggested that VOX formation can be chemically stimulated by reactive Fe species while field studies have provided evidence for direct biological (enzymatic) VOX formation. However, the relative contribution of abiotic and biotic processes to global VOX budgets is still unclear. The goals of this study were to quantify VOX release from sediments from a hypersaline lake in Western Australia (Lake Strawbridge) and to distinguish between the relative contributions of biotic and abiotic VOX formation in microbially active and sterilized microcosms. Our experiments demonstrated that the release of organochlorines from Lake Strawbridge sediments was mainly biotic. Among the organochlorines detected were monochlorinated, e.g., chloromethane (CH₃Cl), and higher chlorinated VOX compounds such as trichloromethane (CHCl₃). Amendment of sediments with either Fe­(III) oxyhydroxide (ferrihydrite) or a mixture of lactate/acetate or both ferrihydrite and lactate/acetate did not stimulate VOX formation. This suggests that although microbial Fe­(III) reduction took place, there was no stimulation of VOX formation via Fe redox transformations or the formation of reactive Fe species under our experimental conditions