Life Sciences Commons^™

A Simple Post-Hoc Method To Add Spatial Context To Predictive Species Distribution Models, Michael B. Ashcroft, Kristine O. French, Laurie A. Chisholm

Faculty of Science - Papers (Archive)

Methods to incorporate spatial context into species distribution models (SDMs) are underutilised, with predictions usually based only on environmental space and ignoring geographic space. The goals of this study were to demonstrate a relatively simple post-hoc method to include spatial context in SDMs and to quantify the improvement over purely niche-based models. The method involved producing a standard niche-based model using established techniques, such as Maxent, and then calculating the neighbourhood average of the model output in geographic space. In effect, we tested whether the spatially averaged model output was better at predicting species distributions than the raw model output. …

Fatty And Volatile Oils Of The Gypsywort Lycopus Europaeus L. And The Gaussian-Like Distribution Of Its Wax Alkanes, Niko Radulovic, Marija Denic, Zorica Stojanovic-Radic, Danielle Skropeta

Faculty of Science - Papers (Archive)

The detailed analyses of the volatile essential oil and lipid profiles of the aerial parts from the blooming and fruit-forming stages of both ripe and unripe fruit of Lycopus europaeus (Lamiaceae) are presented. Both of these profiles are distinguished by components with a restricted occurrence in the Plant Kingdom. These rare compounds include (E)-hotrienol in the volatiles, numerous unusual fatty acids (such as very long chain, odd-numbered and branched-chain) in the bound lipids and a high amount of iso- and anteiso-alkanes in the epicuticular waxes. Furthermore, a Gaussian-like distribution of the relative amounts of the epicuticular wax alkanes was observed. …

Sources, Distribution, And Acidity Of Sulfate-Ammonium Aerosol In The Arctic In Winter-Spring, Jenny A. Fisher, Daniel J. Jacob, Q Wang, Roya Bahreini, C C. Carouge, M J. Cubison, Jack E. Dibb, Thomas Diehl, J L. Jimenez, E M. Leibensperger, Zifeng Lu, Marcel B.J Meinders, H. O T. Pye, Patricia K. Quinn, Sangeeta Sharma, David G. Streets, Aaron Van Donkelaar, R M. Yantosca

Faculty of Science - Papers (Archive)

We use GEOS-Chem chemical transport model simulations of sulfate–ammonium aerosol data from the NASA ARCTAS and NOAA ARCPAC aircraft campaigns in the North American Arctic in April 2008, together with longer-term data from surface sites, to better understand aerosol sources in the Arctic in winter–spring and the implications for aerosol acidity. Arctic pollution is dominated by transport from mid-latitudes, and we test the relevant ammonia and sulfur dioxide emission inventories in the model by comparison with wet deposition flux data over the source continents. We find that a complicated mix of natural and anthropogenic sources with different vertical signatures is …

How Well Do Predators Adjust To Climate-Mediated Shifts In Prey Distribution? A Study On Australian Water Pythons, Beata Ujvari, Rick Shine, Thomas Madsen

Faculty of Science - Papers (Archive)

Climate change can move the spatial location of resources critical for population viability, and a species resilience to such changes will depend upon its ability to flexibly shift its activities away from no-longer-suitable sites to exploit new opportunities. Intuition suggests that vagile predators should be able to track spatial shifts in prey availability, but our data on water pythons (Liasis fuscus) in tropical Australia suggest a less encouraging scenario. These pythons undergo regular long-range (to .10 km) seasonal migrations to follow flooding-induced migrations by their prey (native dusky rats, Rattus colletti ). However, when an extreme flooding event virtually eliminated …

Evidence For Specific Subunit Distribution And Interactions In The Quaternary Structure Of Α-Crystallin, Amie M. Morris, J Andrew Aquilina

Faculty of Science - Papers (Archive)

The quaternary structure of alpha-crystallin is dynamic, a property which has thwarted crystallographic efforts towards structural characterization. In this study, we have used collision-induced dissociation mass spectrometry to examine the architecture of the polydisperse assemblies of alpha-crystallin. For total alpha-crystallin isolated directly from fetal calf lens using size-based chromatography, the alpha B-crystallin subunit was found to be preferentially dissociated from the oligomers, despite being significantly less abundant overall than the alpha A-crystallin subunits. Furthermore, upon mixing molar equivalents of purified alpha A- and alpha B-crystallin, the levels of their dissociation were found to decrease and increase, respectively, with time. Interestingly …

A Multi-Scale Geospatial Study Of Wetlands Distribution And Agricultural Zones, And The Case Of India, N Nagabhatla, Rohan Wickramasuriya, N Prasad, Max Finlayson

Faculty of Science - Papers (Archive)

This paper highlights the global and the regional scale representation of wetlands ecosystems using geospatial tools and multiple data sets. At global scale, the Ramsar database is investigated for representation of the wetlands sites of international importance against the "global agricultural zones" derived from the thematic aggregation of Global Irrigated Area Map databases. The analysis of "Ramsar sites" under cultivation reflects the present trend in wetlands use for agriculture. The scenario is also compared with the historical pattern derived from Vavilov's food zones of 1926. Observed is an aggregate increase in cropped wetlands area from 25% (1926) to 43% (2006). …

Soil Geochemistry And Pathfinder Element Distribution Associated With The Hillgrove Antimony-Gold-Tungsten Deposit, New England Orogen, Nsw, R Ellsmore, Solomon Buckman, C Simpson

Faculty of Science - Papers (Archive)

No abstract provided.

Distribution Of Class 1 Integrons With Is26-Mediated Deletions In Their 3'-Conserved Segments In Escherichia Coli Of Human And Animal Origin., Fay E. Dawes, Alexander Kuzevski, Karl A Bettelheim, Michael A Hornitzky, Steven P Djordjevic, Mark J. Walker

Faculty of Science - Papers (Archive)

Class 1 integrons play a role in the emergence of multi-resistant bacteria by facilitating the recruitment of gene cassettes encoding antibiotic resistance genes. 512 E. coli strains sourced from humans (n = 202), animals (n = 304) and the environment (n = 6) were screened for the presence of the intI1 gene. In 31/79 integron positive E. coli strains, the gene cassette regions could not be PCR amplified using standard primers. DNA sequence analysis of 6 serologically diverse strains revealed atypical integrons harboured the dfrA5 cassette gene and only 24 bp of the integron 3'-conserved segment (CS) remained, due to …

Effect Of Protein Stabilization On Charge State Distribution In Positive- And Negative Ion Electrospray Ionization Mass Spectra, Stephen J. Watt, Margaret Sheil, Jennifer L. Beck, Pavel Prosselkov, Gottfried Otting, Nicholas E. Dixon

Faculty of Science - Papers (Archive)

Changes in protein conformation are thought to alter charge state distributions observed in electrospray ionization mass spectra (ESI-MS) of proteins. In most cases, this has been demonstrated by unfolding proteins through acidification of the solution. This methodology changes the properties of the solvent so that changes in the ESI-MS charge envelopes from conformational changes are difficult to separate from the effects of changing solvent on the ionization process. A novel strategy is presented enabling comparison of ESI mass spectra of a folded and partially unfolded protein of the same amino acid sequence subjected to the same experimental protocols and conditions. …

Impact Of Data Uncertainty On The Spatio-Temporal Distribution Of Australian Cyclones, 1906-2006, Marjetta L. Puotinen

Faculty of Science - Papers (Archive)

Tropical cyclones (known elsewhere as hurricanes or typhoons) regularly track through Australia’s northern coastal regions (Figure 1).

Data documenting the basic characteristics of cyclones in the Australian region is available from the Bureau of Meteorology (BOM) as early as 1906. This data set (freely available in ASCII format at http://www.bom.gov.au) records some 41 attributes (most of which are not complete for the entire time series) for 22,645 individual cyclone eye positions. Because cyclones can cause considerable impact to both marine and terrestrial environments, data sets such as this are widely used to reconstruct past cyclone conditions (for example, see Berz …