Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2006

Faculty of Science - Papers (Archive)

Between

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Demographic Feedback Between Clonal Growth And Fragmentation In An Invasive Seaweed, Jeffrey T. Wright, Andrew R. Davis Jan 2006

Demographic Feedback Between Clonal Growth And Fragmentation In An Invasive Seaweed, Jeffrey T. Wright, Andrew R. Davis

Faculty of Science - Papers (Archive)

Many abundant plants, invertebrates, and seaweed are clonal, and this allows the formation of high-density aggregations, foraging, and the placement of modules into new space, and rapid rates of expansion. For these species, population density and rates of expansion are functions of recruitment of asexual modules and post-recruitment vegetative growth and survivorship. In this study, we provide the first experimental test of the relative importance of these two processes in determining the abundance of a clonal seaweed using Caulerpa taxifolia, an invasive green alga that spreads rapidly and reaches very high abundance. We asked two main questions: What is …


Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, J F. Muller, T Blumenstock, Nicholas B. Jones, David W. Griffith, C P Rinsland, E Mahieu, S Wood, R De Beek, P Demoulin, M Buchwitz, P Duchatelet, C Frankenberg, A Gloudemans, T Kerzenmacher, I Kramer, J Mellqvist, H Shrijver, A Strandberg, D Smale, W Stremme, A G. Straume, R Sussmann, M Van Den Broek, T Wagner, K Strong, Aldona Wiacek, J R. Taylor, Hans Fast, Thorsten Warneke, Richard L. Mittermeier, Justus Notholt, Voltaire A. Velazco Jan 2006

Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, J F. Muller, T Blumenstock, Nicholas B. Jones, David W. Griffith, C P Rinsland, E Mahieu, S Wood, R De Beek, P Demoulin, M Buchwitz, P Duchatelet, C Frankenberg, A Gloudemans, T Kerzenmacher, I Kramer, J Mellqvist, H Shrijver, A Strandberg, D Smale, W Stremme, A G. Straume, R Sussmann, M Van Den Broek, T Wagner, K Strong, Aldona Wiacek, J R. Taylor, Hans Fast, Thorsten Warneke, Richard L. Mittermeier, Justus Notholt, Voltaire A. Velazco

Faculty of Science - Papers (Archive)

Total column amounts of CO, CH4, CO2 and N2O retrieved from SCIAMACHY nadir observations in its near-infrared channels have been compared to data from a ground-based quasi-global network of Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data considered here have been produced by three different retrieval algorithms, WFM-DOAS (version 0.5 for CO and CH4 and version 0.4 for CO2 and N2O), IMAP-DOAS (version 1.1 and 0.9 (for CO)) and IMLM (version 6.3) and cover the January to December 2003 time period. Comparisons have been made for individual data, as well as for monthly averages. To maximize the number of reliable coincidences …


Comparison Of Virulence Gene Profiles Between Escherichia Coli Strains Isolated From Healthy And Diarrheic Swine, Mark R. Wilson, Xi Yang Wu, Idris Barchia, Karl A Bettelheim, Steven Driesen, Darren J. Trott, Toni A. Chapman, James J C Chin Jan 2006

Comparison Of Virulence Gene Profiles Between Escherichia Coli Strains Isolated From Healthy And Diarrheic Swine, Mark R. Wilson, Xi Yang Wu, Idris Barchia, Karl A Bettelheim, Steven Driesen, Darren J. Trott, Toni A. Chapman, James J C Chin

Faculty of Science - Papers (Archive)

A combination of uni- and multiplex PCR assays targeting 58 virulence genes (VGs) associated with Escherichia coli strains causing intestinal and extraintestinal disease in humans and other mammals was used to analyze the VG repertoire of 23 commensal E. coli isolates from healthy pigs and 52 clinical isolates associated with porcine neonatal diarrhea (ND) and postweaning diarrhea (PWD). The relationship between the presence and absence of VGs was interrogated using three statistical methods. According to the generalized linear model, 17 of 58 VGs were found to be significant (P < 0.05) in distinguishing between commensal and clinical isolates. Nine of the 17 genes represented by iha, hlyA, aidA, east1, aah, fimH, iroN(E. coli), traT, and saa have not been previously identified as important VGs in clinical porcine isolates in Australia. The remaining eight VGs code for fimbriae (F4, F5, F18, and F41) and toxins (STa, STb, LT, and Stx2), normally associated with porcine enterotoxigenic E. coli. Agglomerative hierarchical algorithm analysis grouped E. coli strains into subclusters based primarily on their serogroup. Multivariate analyses of clonal relationships based on the 17 VGs were collapsed into two-dimensional space by principal coordinate analysis. PWD clones were distributed in two quadrants, separated from ND and commensal clones, which tended to cluster within one quadrant. Clonal subclusters within quadrants were highly correlated with serogroups. These methods of analysis provide different perspectives in our attempts to understand how commensal and clinical porcine enterotoxigenic E. coli strains have evolved and are engaged in the dynamic process of losing or acquiring VGs within the pig population.