Food utilisation and digestive ability of aquatic and semi-terrestrial crayfishes, Cherax destructor and Engaeus sericatus (Astacidae, Parastacidae)

Both Engaeus sericatus and Cherax destructor are omnivorous crayfishes consuming a variety of food items. Materials identified in the faeces of both E. sericatus and C. destructor consisted of mainly plant material with minor amounts of arthropod animals, algae and fungi. The morphology of the gastric mill of C. destructor suggests that it is mainly involved in crushing of food material while the gastric mill of E. sericatus appears to be better suited to cutting of food material. Given this, the gastric mill of E. sericatus may be better able to cut the cellulose and hemicellulose fibres associated with fibrous plant material. In contrast, the gastric mill of C. destructor appears to be more efficient in grinding soft materials such as animal protein and algae. Both species accumulated high amounts of lipids in their midgut glands (about 60% of the dry mass) which were dominated by triacylglycerols (81–82% of total lipids). The dominating fatty acids were 16:0, 16:1(n-7), 18:1(n-9), 18:2(n-6), and 18:3(n-3). The two latter fatty acids can only be synthesised by plants, and are thus indicative of the consumption of terrestrial plants by the crayfishes. The similarity analysis of the fatty acid patterns showed three distinct clusters of plants and each of the crayfish species. The complement of digestive enzymes, proteinases, total cellulase, endo-β-1,4-glucanase, β-glucosidase, laminarinase and xylanase within midgut gland suggests that both C. destructor and E. sericatus are capable of hydrolysing a variety of substrates associated with an omnivorous diet. Higher activities of total cellulase, endo-β-1,4-glucanase and β-glucosidase indicate that E. sericatus is better able to hydrolyse cellulose within plant material than C. destructor. In contrast to E. sericatus, higher total protease and N-acetyl-β-d-glucosaminidase activity in the midgut gland of C. destructor suggests that this species is better able to digest animal materials in the form of arthropods. Differences in total cellulase and gastric mill morphology suggest that E. sericatus is more efficient at digesting plant material than C. destructor. However, the contents of faecal pellets and the fatty acid compositions seem to indicate that both species opportunistically feed on the most abundant and easily accessible food items.

Utilization of a new bdelloid rotifer (Philodina acuticornis odiosa) assay to evaluate the effect of salinity on the toxicity of chlorothalonil

Acute (24 h) toxicity tests were conducted to determine the toxicity of the fungicide chlorothalonil towards the freshwater bdelloid rotifer (Philodina acuticornis odiosa). Since rotifers are the dominant zooplankton species in many inland freshwater lakes in Australia, the influence of salinity on chlorothalonil toxicty was also assessed. The rotifers used in this study appeared to be reasonably tolerant to changes in salinity, with little mortality observed at 3760 µS cm-1, increasing thereafter at higher salinity. The bdelloid rotifers were, however, found to be highly sensitive to chlorothalonil (24 h LC50, 3.2 µg L-1) with results also suggesting that as salinity increases, so does toxicity (e.g., 24 h LC50 at 5000 µS cm-1, 0.5 µg L-1).

Visionnaire 2010

Visionnaire 2010 : A screening of 15 postgraduate and masters films.

Two hundred and two - Daniella Said, Adam Green, Phoebe Beasley, Juntra Santitarangkun, Olexander Barnes & Rhett Ortlipp.
Gone to see - Sean Rafter.
Hippocratic oath - Nathan Primer, Daniel Merei, Melina Flood, Michael Dearnley, Mathew Karanicolas & Nicholas White.
The other voices - Tania Raouf.
Standover - Nicholas Hancock, Ryan Thomas, David Hurley, Nicholas Weller, Mitch McTaggart & Djorvan Caro.
Sisters - Kailai Gu.
Escape - Jonathan Burton, Simon Todd, Todd Johnson, Amanda Klimos, James Murphy, Ola Gytri & Max Reed.
Welcome to the Anderson's - Maneesha Jacob.
Hannah - Jodi Deutrom, Ardimas Andi, Ben Engeset, Kim Han Law, Steffen Hagen & Timotius.
Hour3 - Akanksha Shakya.
3-25-6 - Syamsul Azhar, Ethan Bottomley, Tiffany Dalton, Kane Gloury, Alexandra Latimer & Lene Moerch.
Seher and others - Bircan Eral.
Edward Barsky - Breidi Boyle, Bree Mansell, Simon DeNatris & Murphy McLachlan.
Detecting Calvin - Kara Tyson, Aimee Linossier, Jessica Ruffino, Seamus Parkinson, Dean Sacco & Simon Holt.
Double date - Adriana Bizzarri, Matthew Smolen, Effie Telianidis, Oliver Kerr, Lucy Ramshaw & Luisa Tascone.

Visionnaire 2011

Visionnaire : A screening of postgraduate and masters films

Play ‘Crack the Sky’ - Steffen Hagen
The Priest - Benjamin Engeset
Sitcom Idiots Inc. - Mitchell McTaggart
Playing for it - Jacinta Adams, Alex Dance, Simone Berman, Esteban Ulloa, James Westland & Jarrod Watters
The boy who lived in the cemetery - Kerina Pereira, Emma Robinson, Tim Mitchell, Helin Kusman & Rebecca Drought
A Burger too far - Scott Burgess, Rhys Salmon, Karina McCowan, Tom McCann, Michael Hales & Aidan Truscott
Crimson Drive - Samantha Kuruvita, Shaun McFadyen, Vegard Dahle, Anja Aasheim, Shehan Vestrheim & Mikael Skramesto
Mikael - Kathleen Lynch, David McKinnar, David Davey, Alex Voltz, Gavin Juchnevicius & Shannon McFarland
A Slight Case of Death - David Laub, Tian Zhang, Janine Evans, Josh Horeau, Jacobo Arenas & Ben Teychenne
Neil - Courtney Gardiner, Rebecca Jacobs, Mark D’Alessandro, Jacob Williams, Trygve Nordhammer & Paul Mooney
Little Donnie Berner - Louise Walsh, Bhare Kesmaei, Matthew Skibicki, Krister Svensli & Nicholas Issell
Intervention - Georgie Thomas, Allison Flanagan, Allison Erlanger, Fredrik Waldeland, Torkild Ziegler & Brad Smith
Vicissitudes - Ben Mix, Sinead Lau, Claire Patterson, Joel Buncle, James Magree & Thomas Boarder

A new model to imitate the foraging behavior of Physarum polycephalum on a nutrient-poor substrate

Researches on Physarum polycephalum show that methods inspired by the primitive unicellular organism can construct an efficient network and solve some complex problems in graph theory. Current models simulating the intelligent behavior of Physarum are mainly based on Hagen-Poiseuille Law and Kirchhoff Law, reaction-diffusion, Cellular Automaton and multi-agent approach. In this paper, based on an assumption that the plasmodium of Physarum forages for food along the gradient of chemo-attractants on a nutrient-poor substrate, a new model is proposed to imitate its intelligent foraging behavior. The key point of the model is that the growth of Physarum is determined by the simple particle concentration field relating the distance to food source and the shape of food source on a nutrient-poor substrate. To verify this model, numerical experiments are conducted according to Adamatzky[U+05F3]s experiment. Results in spanning tree construction by this model are almost the same as those of Physarum and Oregonator model. The proposed model can also imitate Physarum to avoid repellents. Furthermore, the Euclidean Spanning tree built by this model is similar to its corresponding Minimal Euclidean Spanning tree.