Spatial subdivision among assemblages of Spanish mackerel, Scomberomorus commerson (Pisces: Scombridae) across northern Australia: implications for fisheries management

Aim: This study investigated the use of stable δ13C and δ18O isotopes in the sagittal otolith carbonate of narrow-barred Spanish mackerel, Scomberomorus commerson, as indicators of population structure across Australia. Location: Samples were collected from 25 locations extending from the lower west coast of Western Australia (30°), across northern Australian waters, and to the east coast of Australia (18°) covering a coastline length of approximately 9500 km, including samples from Indonesia. Methods: The stable δ13C and δ18O isotopes in the sagittal otolith carbonate of S. commerson were analysed using standard mass spectrometric techniques. The isotope ratios across northern Australian subregions were subjected to an agglomerative hierarchical cluster analysis to define subregions. Isotope ratios within each of the subregions were compared to assess population structure across Australia. Results: Cluster analysis separated samples into four subregions: central Western Australia, north Western Australia, northern Australia and the Gulf of Carpentaria and eastern Australia. Isotope signatures for fish from a number of sampling sites from across Australia and Indonesia were significantly different, indicating population separation. No significant differences were found in otolith isotope ratios between sampling times (no temporal variation). Main conclusions: Significant differences in the isotopic signatures of S. commerson demonstrate that there is unlikely to be any substantial movement of fish among these spatially discrete adult assemblages. The lack of temporal variation among otolith isotope ratios indicates that S. commerson populations do not undergo longshore spatial shifts in distribution during their life history. The temporal persistence of spatially explicit stable isotopic signatures indicates that, at these spatial scales, the population units sampled comprise functionally distinct management units or separate ‘stocks’ for many of the purposes of fisheries management. The spatial subdivision evident among populations of S. commerson across northern and western Australia indicates that it may be advantageous to consider S. commerson population dynamics and fisheries management from a metapopulation perspective (at least at the regional level).

Wastewater remediation options for prawn farms - Aquaculture Industry Development Initiative 2002-04.

There are many potential bioremediation approaches that may be suitable for prawn farms in Queensland. Although most share generally accepted bioremediation principles, advocacy for different methods tends to vary widely. This diversity of approach is particularly driven by the availability and knowledge of functional species at different localities around the world. In Australia, little is known about the abilities of many native species in this regard, and translocation and biosecurity issues prevent the use of exotic species that have shown potential in other countries. Species selected must be tolerant of eutrophic conditions and ecological shifts, because prawn pond nutrient levels and pathways can vary with different assemblages of autotrophic and heterotrophic organisms. Generally, they would be included in a constructed ecosystem because of their functional contributions to nutrient cycling and uptake, and to create nutrient sinks in forms of harvestable biomass. Wide salinity, temperature and water quality tolerances are also valuable attributes for selected species due to the sometimes-pronounced effects of environmental extremes, and to provide over-wintering options and adequate safety margins in avoiding mass mortalities. To practically achieve these bioremediation polycultures on a large scale, and in concert with the operations of a prawn farm, methods involving seed production, stock management, and a range of other farm engineering and product handling systems need to be reliably achievable and economically viable. Research funding provided by the Queensland Government through the Aquaculture Industry Development Initiative (AIDI) 2002-04 has enabled a number of technical studies into biological systems to treat prawn farm effluent for recirculation and improved environmental sustainability. AIDI bioremediation research in southern Queensland was based at the Bribie Island Aquaculture Research Centre (BIARC), and was conducted in conjunction with AIDI genetics and selection research, and a Natural Heritage Trust (NHT) funded program (Coast and Clean Seas Project No.717757). This report compilation provides a summary of some of the work conducted within these programs.

Synthesis and physico-chemical properties of diruthenium(III, II) tetra-aryl carboxylato compounds

Monochloro-tetra-μ-aryl-carboxylatodiruthenium(III, II) compounds Ru2Cl (O2CAr)4 (Ar = -C6H5; -C6H4-p-OCH3), are prepared and characterized. The compounds have magnetic moments that correspond to three unpaired spins per dimer. The Rusingle bondRu bond order is 2.5 and the ground electronic configuration is σ2π4δ2(δ*π*)3. The visible spectral band is observed at ca 450 nm along with a shoulder near 580 nm in DMF solution. The compounds undergo a one-electron Ru(III)Ru(II) → Ru(II)Ru(II) quasi-reversible reduction in DMF near 0.0 V vs sce.

Managing the grass-legume balance in Stylosanthes scabra cv. Seca pastures in central Queensland

The impacts of 4 grazing strategies (year-long grazing, summer grazing, winter grazing and winter grazing plus spring burning) on the grass:legume balance were studied between 2000 and 2006 in a pasture oversown with Stylosanthes scabra cv. Seca (Seca stylo) in central Queensland. Seasonal rainfall throughout the study was generally below average. Total pasture yields in autumn were higher in the 2 winter grazing than the 2 summer grazing treatments, largely reflecting the sampling time relative to when grazing occurred. There were few differences in Seca composition in autumn, although there was a clear trend for Seca composition to be reduced by winter grazing plus burning. Both the frequency of occurrence and plant density of Seca were higher under the 2 summer grazing treatments and there was also a trend for the density of juvenile plants (<5 cm height) to be higher in the 2 summer grazing treatments. Seca soil seed banks were generally low and were reduced in the winter grazing plus burning treatment in spring 2002. The frequency of the palatable perennial grass Pennisetum ciliaris (Biloela buffel grass) was reduced while that of the 'increaser' species Bothriochloa pertusa (Indian couch grass) and Stachytarpheta jamaicensis (snake weed) increased in the 2 summer grazing treatments compared with the 2 winter grazing treatments. Burning in spring increased soil loss in treatments grazed in winter. Differences in Seca frequency and density but not composition were explained by the 2 summer grazing treatments promoting 'gaps' in the pasture which were then colonised by Seca plants and other 'increaser' species. It was reasoned that, with time, mature Seca plants in the 2 winter grazing treatments would die so that Seca composition would eventually become higher under summer grazing regimes than under winter grazing. It was concluded that limiting grazing to particular seasons can alter legume:grass balance and that a time-frame of 5-8 years with average to good rainfall would be necessary to achieve large shifts in composition.

Purification and partial characterization of microsomal cytochrome b555 from the higher plant Catharanthus-Roseus

Microsomal b-type hemoprotein designated, cytochrome b555 of C-Roseus seedlings was solubilized using detergents and purified by a combination of ion exchange chromatography and gel filtration to a specific content of 18.5 nmol per mg of protein. The purified cytochrome b555 was homogeneous and estimated to have an apparent molecular weight of 16500 on SDS-PAGE. The absorption spectrum of the reduced form has major peaks at 424, 525 and 555 nm. The α-band of the reduced form is asymmetric with a pronounced shoulder at 559 nm. The spectrum of the pyridine ferrohemochrome shows absorption peaks at 557, 524 and 418 nm indicating that the cytochrome has protoheme prosthetic group. The purified cytochrome is autoxidizable and does not combine with carbon monoxide, azide or cyanide. It is reducible by NADH in the presence of NADH-cytochrome b555 reductase partially purified from C-Roseus microsomes.

Solid state and solution conformation of Boc-L-Met-Aib-L-Phe-OMe. Beta-turn conformation of a sequence related to an active chemotactic peptide analog

The conformation of the peptide Boc-L-Met-Aib-L-Phe-OMe has been studied in the solid state and solution by X-ray diffraction and 1H n.m.r., respectively. The peptide differs only in the N-terminal protecting group from the biologically active chemotactic peptide analog formyl-L-Met-Aib-L-Phe-OMe. The molecules adopt a type-II beta-turn in the solid state with Met and Aib as the corner residues (phi Met = -51.8 degrees, psi Met = 139.5 degrees, phi Aib = 58.1 degrees, psi Aib = 37.0 degrees). A single, weak 4----1 intramolecular hydrogen bond is observed between the Boc CO and Phe NH groups (N---O 3.25 A, N-H---O 128.4 degrees). 1H n.m.r. studies, using solvent and temperature dependencies of NH chemical shifts and paramagnetic radical induced line broadening of NH resonances, suggest that the Phe NH is solvent shielded in CDCl3 and (CD3)2SO. Nuclear Overhauser effects observed between Met C alpha H and Aib NH protons provide evidence of the occurrence of Met-Aib type-II beta-turns in these solvents.

Infrared spectra of 1.3-dithiole-2-thione and its selenium analogues ând frequency assignment and molecular force constants

Infrared spectra of 1,3-dithiole-2-thione (DTT) and its four selenium analogues have been studied in the region 4000 to 20 cm�1. Assignment of all the fundamental frequencies was made by noting the band shifts on progressive selenation. Normal coordinate analysis procedures have been applied for both in-plane and out-of-plane vibrations to help the assignments. The Urey�Bradley force function supplemented with valence force constants for the out-of-plane vibrations was employed for coordinate calculations. A correlation of the infrared assignments of DTT with its different selenium analogues is accomplished. Further, the infrared assignments are compared with those of trithiocarbonate ion and its selenium analogues and other structurally related heterocyclic molecules.

1H and 13C nuclear magnetic resonance studies on X-537A (lasalocid-A)-calcium complexes: observation of a sandwich complex

Studies on the conformational and binding characteristics of the ionophoric antibiotic X-537A (lasalocid-A)�calcium ion complexes have been carried out in deuteriated acetonitrile (CD3 CN) using proton and carbon-13 nuclear magnetic resonance (1 H and 13C n.m.r.) spectroscopy. Detailed analysis of the salt-induced chemical shifts at various X-537A to calcium concentration ratios indicated that X-537A forms charged complexes with calcium with 2 : 1 and 1 : 1 stoicheiometries. The conformational model for the complex based on the n.m.r. data showed that the calcium ion is preferentially bound to one end of the molecule, which is binding to three oxygen atoms, the other end (the salicylic acid part) being relatively free. In the 2 : 1 (sandwich) complex, the calcium ion is sandwiched between two X-537A molecules with three oxygen atoms binding to it from each molecule.

Surface-enhanced Raman scattering of molecules adsorbed on nanocrystalline Au and Ag films formed at the organic-aqueous interface

Surface-enhanced Raman scattering (SERS) of pyridine adsorbed on ultrathin nanocrystalline Au and Ag films generated at the liquid-liquid interface has been investigated. The shifts and intensification of bands formed with these films comprising metal nanoparticles are comparable to those found with other types of Au and Ag substrates. SERS of rhodamine 6G adsorbed on Ag films has also been studied. The results demonstrate that nanocrystalline metal films prepared by the simple method involving the organic-aqueous interface can be used effectively for SERS investigations.

Molecular-complexes of metallo tetraphenyl porphyrins with 2,4,5,7-tetranitro fluorenone

The interactions of mesotetraphenyl porphyrin and its metallo derivatives with 2,4,5,7-tetra nitrofluorenone have been studied using spectroscopic methods. The association constants (K) for 1:1 complexes in Ch2Cl2Cl2 follow the order Pd+2>Co+2> Cu+2>VO+2>Ni+2>Zn+2. The values of K are accounted in terms of stereochemistry of MTPPs and the electronic configuration of the metal ions. The magnitude and direction of the proton NMR shifts of the acceptor and donor in the complexes and their ESR parameter furnish information as to the possible structures of these complexes in solution.

Forces shaping the future of work in a changing regional economy

This paper presents research which examined perceptions on the future of work in Queensland. It highlights the major drivers of change including: changing technology, demographics, increasing globalisation and economic shifts. Focus groups were conducted and findings show that Queensland businesses are acutely aware of the coming changes, but are less certain about how to respond. Current good practices plus recommendations for the future - particularly the lead role government and industry bodies need to play - are discussed. These recommendations will support Queensland businesses to thrive and adapt to the forces shaping work in this changing regional economy.

1H and 13C NMR spectral studies of C-2 substituted isomeric exo- and endo-5-methyl-bicyclo[3.2.1]octane-6,8-diones

A detailed analysis of the 1H and 13C NMR spectra of C-2 aryl and alkyl/desalkyl substituted isomeric exo- and endo-5-methylbicyclo[3.2.1]octane-6,8-diones is presented. The chemical shift of the C-5 angular methyl, the C-2 alkyl/olefinic (C-10)/C-2 methine protons, the aromatic proton shieldings and the characteristic AMX and ABX spectral pattern of the ketomethylene and bridgehead protons were found to be sensitive to the phenyl ring orientation (anisotropy). These distinctive features could be used for configurational distinction for this class of compounds. With increasing ortho-methoxy substitution on the phenyl ring, considerable deshilelding of the bridgehead proton was observed (ca. 0.6 ppm). Absence of the C-2 alkyl group in the desalkyl isomers resulted in substantial changes in the chemical shifts of different protons. A study of the NMR spectra of the corresponding bicyclic compounds with C-2 methoxy/hydroxy substitution instead of the aryl group revealed that the anisotropy of the phenyl ring and the electronegative oxygen substituents have opposite effects. The 13C NMR spectral assignment of each carbon resonance of C-2 aryl and alkyl/desalkyl substituted isomeric exo- and endo-5-methylbicyclo[3.2.1]octane-6,8-diones and the corresponding C-2 methoxy/hydroxy/chloro and methyl bicyclic compounds are reported. Additional ortho-methoxy substitution on the phenyl ring was found to produce considerable high field shifts of the C-10 and C-1 carbon resonances. A high-field shift was observed for the C-6 and C-8 carbonyl carbons, presumably due to 1,3-dicarbonyl interactions. The chemical shifts of C-1 aromatic, C-10 alkyl and C-2 carbons, which are sensitive to exo/endo isomerism, could be utilized in differentiating a pair of isomers.

Farewelling the regent: Considering 'festival memory' in the face of innovation and change

The rapid expansion of the international film festival circuit has included the loss of smaller, but well established festivals, often due to the perceived need for constant innovation and change. The Brisbane International Film Festival was founded in 1992. After considerable disruption to the festival’s leadership, programme and location due to economic and socio-political changes, it was held for the last time in 2013. Nafus and Anderson cite the term ‘lieux de memoire’, meaning ‘sites of memory’, as a place of “remembrance that exist(s) in a social world that constantly seeks to get ahead of itself, to “innovate” (Nafus and Anderson in Cefkin 2009, 141). The concept of ‘festival memory’ has not yet been explored in any depth, but such significant shifts in festivals such as BIFF are arguably sites where festival histories and identities, and film knowledge itself, can be irretrievably lost.

The intrinsic plasticity of farm businesses and their resilience to change. An Australian example.

This paper examines the idea that plasticity in farm management introduces resilience to change and allows farm businesses to perform when operating in highly variable environments. We also argue for the need to develop and apply more integrative assessments of farm performance that combine the use of modelling tools with deliberative processes involving farmers and researchers in a co-learning process, to more effectively identify and implement more productive and resilient farm businesses. In a plastic farming system, farm management is highly contingent on environmental conditions. In plastic farming systems farm managers constantly vary crops and inputs based on the availability of limited and variable resources (e.g. land, water, finances, labour, machinery, etc.), and signals from its operating environment (e.g. climate, markets), with the objective of maximising a number of, often competing, objectives (e.g. maximise profits, minimise risks, etc.). In contrast in more rigid farming systems farm management is more calendar driven and relatively fixed sequences of crops are regularly followed over time and across the farm. Here we describe the application of a whole farm simulation model to (i) compare, in silico, the sensitivity of two farming systems designs of contrasting levels of plasticity, operating in two contrasting environments, when exposed to a stressor in the form of climate change scenarios;(ii) investigate the presence of interactions and feedbacks at the field and farm levels capable of modifying the intensity and direction of the responses to climate signals; and (iii) discuss the need for the development and application of more integrative assessments in the analysis of impacts and adaptation options to climate change. In both environments, the more plastic farm management strategy had higher median profits and was less risky for the baseline and less intensive climate change scenarios (2030). However, for the more severe climate change scenarios (2070), the benefit of plastic strategies tended to disappear. These results suggest that, to a point, farming systems having higher levels of plasticity would enable farmers to more effectively respond to climate shifts, thus ensuring the economic viability of the farm business. Though, as the intensity of the stress increases (e.g. 2070 climate change scenario) more significant changes in the farming system might be required to adapt. We also found that in the case studies analysed here, most of the impacts from the climate change scenarios on farm profit and economic risk originated from important reductions in cropping intensity and changes in crop mix rather than from changes in the yields of individual crops. Changes in cropping intensity and crop mix were explained by the combination of reductions in the number of sowing opportunities around critical times in the cropping calendar, and to operational constraints at the whole farm level i.e. limited work capacity in an environment having fewer and more concentrated sowing opportunities. This indicates that indirect impacts from shifts in climate on farm operations can be more important than direct impacts from climate on the yield of individual crops. The results suggest that due to the complexity of farm businesses, impact assessments and opportunities for adaptation to climate change might also need to be pursued at higher integration levels than the crop or the field. We conclude that plasticity can be a desirable characteristic in farming systems operating in highly variable environments, and that integrated whole farm systems analyses of impacts and adaptation to climate change are required to identify important interactions between farm management decision rules, availability of resources, and farmer's preference.

A multi-faceted approach for quantifying the estuarine-nearshore transition in the life cycle of the bull shark, Carcharhinus leucas.

Understanding the ontogenetic habitat linkages of sharks is important for conservation and managing human interactions. We used acoustic telemetry, catch data, elemental and stable isotope signatures and dietary analyses to investigate ontogenetic habitat use in south-east Queensland, Australia, by the bull shark Carcharhinus leucas, a IUCN 'near-threatened' species that is implicated in many shark attacks on humans in urban estuaries. Sequential analyses for delta(15)N and delta(13)C of vertebrae from five adult C. leucas and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) for elemental composition from 23 C. leucas, including a pregnant female, were also used to trace ontogenetic habitat dependence. Acoustic telemetry indicated large juvenile and subadult C. leucas remained in estuarine habitats. delta(15)N values across shark vertebrae showed an ontogenetic shift in diet with total length (TL), confirmed by stomach contents. LA-ICPMS data reflected the ontogenetic movements of C. leucas from natal habitats. Differences among adults were gender related. Shifts in habitat use by subadults were correlated with a sigmoidal delta(13)C relationship with TL. C. leucas have a multipartite, stage-specific dependency in their transition between habitats along the freshwater-estuarine-marine continuum, making them particularly susceptible to the habitat alteration that is occurring globally.