The relationship between membrane damage, release of protein and loss of viability in Escherichia coli exposed to high hydrostatic pressure

The aim of this work was to examine a possible association between resistance of two Escherichia coli strains to high hydrostatic pressure and the susceptibility of their cell membranes to pressure-induced damage. Cells were exposed to pressures between 100 and 700 MPa at room temperature (~20C) in phosphate-buffered-saline. In the more pressure-sensitive strain E. coli 8164, loss of viability occurred at pressures between 100 MPa and 300 MPa and coincided with irreversible loss of membrane integrity as indicated by uptake of propidium iodide (PI) and leakage of protein of molecular mass between 9 and 78 kDa from the cells. Protein release increased to a maximum at 400 MPa then decreased, possibly due to intracellular aggregation at the higher pressures. In the pressure-resistant strain E. coli J1, PI was taken up during pressure treatment but not after decompression indicating that cells were able to reseal their membranes. Loss of viability in strain J1 coincided with the transient loss of membrane integrity between approximately 200 MPa and 600 MPa. In E. coli J1 leakage of protein occurred before loss of viability and the released protein was of low molecular mass, between 8 and 11 kDa and may have been of periplasmic origin. In these two strains differences in pressure resistance appeared to be related to differences in the ability of their membranes to withstand disruption by pressure. However it appears that transient loss of membrane integrity during pressure can lead to cell death irrespective of whether cells can reseal their membranes afterwards

Chancen und perspektiven computergestützter lexikographie.

Ingrid Lemberg, Bernhard Schröder and Angelika Storrer (Editors). Chancen und Perspektiven computergestützter Lexikographie. Lexicogra-phica. Series Maior 107. 2001, 270 pp. ISBN 3-484-39107-3. Tübingen: Max Niemeyer. Price: € 72

Are there Carbon Savings from US Biofuel Policies? Accounting for Leakage in Land and Fuel Markets

This paper applies the insights of the carbon leakage literature to study the emissions consequences of biofuel policies. We develop a simple analytic framework to decompose the intended emissions impacts of biofuel policy from four sources of carbon leakage: domestic fuel markets, domestic land markets, world land markets and world crude oil markets. A numerical simulation model illustrates the magnitude of each source of leakage for combinations of two current US biofuel policies: the Volumetric Ethanol Excise Tax Credit (VEETC) and the Renewable Fuel Standard (RFS). In the presence of both land and fuel market leakage, current US biofuel policies are unlikely to reduce greenhouse gases. Four of the five policy scenarios we consider lead to increases in greenhouse gas emissions. That is, total leakage was greater than 100%. The single scenario that generates emissions savings, the removal of the VEETC in conjunction with a binding RFS, only does so because negative leakage in the domestic fuel market offset the remaining positive sources of leakage.Multi-market, carbon leakage, biofuels, greenhouse gases, Agricultural and Food Policy, Land Economics/Use, Resource /Energy Economics and Policy, Q42, Q54, Q58,

The meeting of worlds: postcolonialism and the game-worlds of Myst

Thesis (M.A.) University of Alaska Fairbanks, 2013Remembered for its lush visuals and its impenetrable puzzles, Myst (1993) was a groundbreaking series whose influence on the medium of digital games can still be felt today. Weaving storytelling and puzzle-solving together, Myst constructs an elaborate transmedial family saga rife with issues of imperial conquest and subjugation the joy of exploration mingled with the destructive forces that arise from the meeting of worlds. But while the narrative material alone is rich enough for analysis, it only becomes more significant when viewed in relation to the nature of the games. By avoiding all reference to their own gameness, and by situating the player as merely a pair of disembodied eyes within the environment, the games allow for deep immersion in a fantastical world with its own internal coherence a world that offers the player the chance to become a virtual, bodiless tourist, venturing into a realm of infinite exotic landscapes to be visually consumed and conquered. Thus the appeal of the game itself is correlated with the postcolonial power-conflicts at the heart of the narrative a connection that raises questions not only about the relationship of game and narrative, but also about the source of our desire for "Myst-like" games.Introduction -- Using the hypertext -- Conclusion -- "The meeting of worlds" DVD (or supplemental files) -- Appendix

Exploring Artist Residencies for Academic Libraries

This white paper describes the results of a research leave that explored artist residencies and considered their potential in academic libraries

JMU Libraries Magazine: Volume 2

Volume 2 of the biennial JMU Libraries magazine, highlighting services, events, awards of the JMU Libraries

Toward an optimal search strategy of optical and gravitational wave emissions from binary neutron star coalescence

Observations of an optical source coincident with gravitational wave emission detected from a binary neutron star coalescence will improve the confidence of detection, provide host galaxy localisation, and test models for the progenitors of short gamma ray bursts. We employ optical observations of three short gamma ray bursts, 050724, 050709, 051221, to estimate the detection rate of a coordinated optical and gravitational wave search of neutron star mergers. Model R-band optical afterglow light curves of these bursts that include a jet-break are extrapolated for these sources at the sensitivity horizon of an Advanced LIGO/Virgo network. Using optical sensitivity limits of three telescopes, namely TAROT (m=18), Zadko (m=21) and an (8-10) meter class telescope (m=26), we approximate detection rates and cadence times for imaging. We find a median coincident detection rate of 4 yr^{-1} for the three bursts. GRB 050724 like bursts, with wide opening jet angles, offer the most optimistic rate of 13 coincident detections yr^{-1}, and would be detectable by Zadko up to five days after the trigger. Late time imaging to m=26 could detect off-axis afterglows for GRB 051221 like bursts several months after the trigger. For a broad distribution of beaming angles, the optimal strategy for identifying the optical emissions triggered by gravitational wave detectors is rapid response searches with robotic telescopes followed by deeper imaging at later times if an afterglow is not detected within several days of the trigger.Comment: 6 pages, 1 figure, Accepted for publication in MNRAS Letters (2011 April 22