Life cycle assessment of energy self-sufficiency systems based on agricultural residues for organic arable farms.

The agricultural industry today consumes large amounts of fossil fuels. This study used consequential life cycle assessment (LCA) to analyse two potential energy self-sufficient systems for organic arable farms, based on agricultural residues. The analysis focused on energy balance, resource use and greenhouse gas (GHG) emissions. A scenario based on straw was found to require straw harvest from 25% of the farm area; 45% of the total energy produced from the straw was required for energy carrier production and GHG emissions were reduced by 9% compared with a fossil fuel-based reference scenario. In a scenario based on anaerobic digestion of ley, the corresponding figures were 13%, 24% and 35%. The final result was sensitive to assumptions regarding, e.g., soil carbon content and handling of by-products.

Exobiology, SETI, von Neumann and geometric phase control.

The central difficulties confronting us at present in exobiology are the problems of the physical forces which sustain three-dimensional organisms, i.e., how one dimensional systems with only nearest interaction and two dimensional ones with its regular vibrations results in an integrated three-dimensional functionality. For example, a human lung has a dimensionality of 2.9 and thus should be measured in m2.9. According to thermodynamics, the first life-like system should have a small number of degrees of freedom, so how can evolution, via cycles of matter, lead to intelligence and theoretical knowledge? Or, more generally, what mechanisms constrain and drive this evolution? We are now on the brink of reaching an understanding below the photon level, into the domain where quantum events implode to the geometric phase which maintains the history of a quantum object. Even if this would exclude point to point communication, it could make it possible to manipulate the molecular level from below, in the physical scale, and result in a new era of geometricised engineering. As such, it would have a significant impact on space exploration and exobiology.

New non-invasive techniques for crew health monitoring in space.

The present paper discusses some of the available non-invasive methods that are currently being evaluated at the University of Sheffield. Applied potential tomography (APT) has considerable potential as an imaging system (albeit of low resolution), which can be readily transferable to the space environment and provide information on fluid shifts on insertion into, and subsequently adaptation to, microgravity. Modern biochemical methods for the analysis of urine can provide information on many aspects of metabolic activity. The monitoring of bone formation and resorption is particularly relevant to space. The bodies handling of food can additionally be investigated by monitoring non-invasively the transit of contents through the gastrointestinal tract. These and other non-invasive monitoring techniques offers to move space medicine closer to clinical observation systems used on earth.

Biophysics in space.

Biophysics is an interdisciplinary field of study where various disciplines work together, with results of much interest to many scientists and students of the life sciences. Since physics is not always accessible to and understandable to biologists and life sometimes too simplified, this presentation focusses on models to help understand the biological effects of space factors, with emphasis on free radicals.

Bidirectional axonal transport of thallium in frog sciatic nerve.

Bidirectional axonal transport of radioactivity was demonstrated in frog sciatic nerve in vitro and in vivo after local application of the thallium isotope 204Tl+ to the nerve. The transport rate was similar in both directions and about 30 min/day at 18 degrees C. The transport was depressed by 2,4-DNP, low-temperature and vinblastine. A somewhat larger amount of radioactivity was transported in the retrograde than in the anterograde direction. The possibility that K+ is in part replaced by Tl+, which is transported bound to organelles, e.g. mitochondria, will be considered. Thallium might be a useful tool for future studies of axonal transport.

Concurrent intracranial self-stimulation and amphetamine self-administration in rats.

In a two-lever testing chamber, rats had concurrent access to intravenous amphetamine and brain stimulation reinforcers. Responding for each reinforcer was generally increased above baseline rates taken when only one reinforcer was available. Amphetamine stereotypy was observed, but did not interfere with rapid lever-pressing for brain stimulation.