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Feature  Protein Crystallisation Diagnostic Facility (PCDF)
The Protein Crystallisation Diagnostics Facility (PCDF) is a multi-user instrument for the fundamental study of the processes of nucleation and crystallisation of biological macro-molecules, and specifically, how these processes are influenced by gravity.
This instrument may be utilised to conduct detailed measurements of physical phenomena in individual reactors, and to control these phenomena through changes in temperature and concentration of solution. The PCDF is an instrument for accommodation in the European Drawer Rack multi-user facility. Accommodation & Transport The electronics unit is housed within an International Sub-rack Standard drawer (ISIS drawer), and was launched integrated within the European Drawer Rack facility. The European Drawer Rack was launched inside the Columbus laboratory. The processing unit is accommodated within the Shuttle's middeck locker, and is launched already outfitted with its initial set of four reactors (either batch or dialysis type). The advantage of this approach is that several of the Space Shuttle middeck accommodation slots can provide power to the locker during the transportation to and from the International Space Station - the processing unit requires power during the ascent and descent phases. Operational Concept The Protein Crystallisation Diagnostics Facility consists of a processing unit and an electronics unit. The processing unit contains a process chamber into which are placed experiment boxes containing reactors (each containing an experiment solution together with the reactor control electronics). The experiment boxes also include drive systems for the individual injection of solutions into the reactors, complemented by a stirrer for solution agitation. Diagnostics are provided within the process chamber, or may be installed directly within the experiment boxes. The electronics unit accommodates all of the controls necessary for the performing the experiments. The possible modes of operation of the instrument are:
The processing unit normally remains on-orbit for a complete mission increment, usually of three months, after which time it is returned to the ground in the Space Shuttle. The electronics unit is expected to remain onboard the International Space Station for between 2 to 3 years. When on the ground, the experiment boxes within the processing unit may be exchanged for a new set. Following removal of the crystals in a temperature-controlled ground laboratory, the reactors are emptied, cleaned, and re-filled with a fresh solution in readiness for the next flight campaign. Data and digital video images are either stored onboard the International Space Station, or transmitted to the ground control station, depending on the transmission capabilities at the time of the experiment. Video images (including microscope images and interferogrammes) can be stored in the host facility (e.g. the European Drawer Rack) video subsystem. When a suitable communication link becomes available, this data may then be transmitted to the ground, and forwarded to the respective investigators. Utilisation scenario The utilisation scenario for the Protein Crystallisation Diagnostics Facility is based on that of the European Drawer Rack - the host facility. This operations scenario relies upon a high degree of cooperation between the supporting ground facilities. These include the Facility Responsible Centre that is in overall charge of the facility, together with the User Home Bases, from which each customer will support their own individual experiment(s). The master timeline is derived from the European Drawer Rack operations plan as defined by the Facility Responsible Centre together with the involved User Home Bases. The main objective of the operations plan is to match the required resources with those available from the Columbus Laboratory to maximise the number of experiments that can operate concurrently. Schedule
The Protein Crystallisation Diagnostics Facility is accomodated in the European Drawer Rack (EDR). EDR was launched into space inside the European Columbus laboratory in February 2008. Last update: 19 March 2009
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