943 resultados para SR– (R–, RC–, EF–) Proximities


Relevância:

20.00% 20.00%

Publicador:

Resumo:

We examine the microchemistry of otoliths of cohorts of a fished shed population of the large catadromous fish, barramundi Lates calcarifer from the estuary of a large tropical river. Barramundi from the estuary of the large, heavily regulated Fitzroy River, north eastern Australia were analysed by making transects of 87Sr/86Sr isotope and trace metal/Ca ratios from the core to the outer edge. Firstly, we examined the Sr/Ca, Ba/Ca, Mg/Ca and Mn/Ca and 87Sr/86Sr isotope ratios in otoliths of barramundi tagged in either freshwater or estuarine habitats that were caught by the commercial fishery in the estuary. We used 87Sr/86Sr isotope ratios to identify periods of freshwater residency and assess whether trace metal/Ca ratios varied between habitats. Only Sr/Ca consistently varied between known periods of estuarine or freshwater residency. The relationships between trace metal/Ca and river flow, salinity, temperature were examined in fish tagged and recaptured in the estuary. We found weak and inconsistent patterns in relationships between these variables in the majority of fish. These results suggest that both individual movement history within the estuary and the scale of environmental monitoring were reducing our ability to detect any patterns. Finally, we examined fish in the estuary from two dominant age cohorts (4 and 7 yr old) before and after a large flood in 2003 to ascertain if the flood had enabled fish from freshwater habitats to migrate to the estuary. There was no difference in the proportion of fish in the estuary that had accessed freshwater after the flood. Instead, we found that larger individuals with each age cohort were more likely to have spent a period in freshwater. This highlights the need to maintain freshwater flows in rivers. About half the fish examined had accessed freshwater habitats before capture. Of these, all had spent at least their first two months in marine salinity waters before entering freshwater and some did not enter freshwater until four years of age. This contrasts with the results of several previous studies in other parts of the range that found that access to freshwater swamps by larval barramundi was important for enhanced population productivity and recruitment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

3-D KCL are equations of evolution of a propagating surface (or a wavefront) Omega(t), in 3-space dimensions and were first derived by Giles, Prasad and Ravindran in 1995 assuming the motion of the surface to be isotropic. Here we discuss various properties of these 3-D KCL.These are the most general equations in conservation form, governing the evolution of Omega(t) with singularities which we call kinks and which are curves across which the normal n to Omega(t) and amplitude won Omega(t) are discontinuous. From KCL we derive a system of six differential equations and show that the KCL system is equivalent to the ray equations of 2, The six independent equations and an energy transport equation (for small amplitude waves in a polytropic gas) involving an amplitude w (which is related to the normal velocity m of Omega(t)) form a completely determined system of seven equations. We have determined eigenvalues of the system by a very novel method and find that the system has two distinct nonzero eigenvalues and five zero eigenvalues and the dimension of the eigenspace associated with the multiple eigenvalue 0 is only 4. For an appropriately defined m, the two nonzero eigenvalues are real when m > 1 and pure imaginary when m < 1. Finally we give some examples of evolution of weakly nonlinear wavefronts.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Consumers today are presented with an increasing array of products. The growing competition for consumer expenditure requires a whole of supply chain approach to maintain market share for existing cultivars and to successfully commercialise new cultivars. The supply chain needs to deliver value and satisfaction to the end customer and profitability to their members. Critical to getting the product right is developing inherent robustness into the cultivar, and developing processes and systems through the whole supply chain that maintain product quality and add value. This paper describes the approach we have used in working with supply chains in Australia and Indonesia to identify priority areas for improvement. Our experience demonstrates the need for a champion in the supply chain with significant influence and a desire to improve. The paper also describes our approach towards improving a specific supply chain to achieve successful commercialisation of a new cultivar. The cultivar was primarily selected for good production characteristics and attractive visual appeal. The performance of the fruit is being monitored from farm to retail shelf to identify points where quality is lost and practices can be improved. A targeted R&D program is investigating ways of improving production efficiency (nutrition, flowering and canopy management), maturity standards to optimise flavour, harvesting and packing practices to reduce skin damage, and ripening and handling practices to optimise shelf life. This integrated approach is based on similar approaches used to improve the performance of existing mango and avocado cultivars.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

the heats of reaction of an oxygen-balanced ternary fuel-oxidizer system have been shown to be linearly related to the total oxidizing valences (P0) of the composition. Because calculation of P0 is simple, the method is found to help in evaluating the energetics of such systems. The accuracy of the method when applied to various ternary systems has been discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the opening pages of Selling Sex we are introduced to 'Joy', a statue of a young female sex worker which stood in East Sydney for eighteen months during 1995- 1997. Following complaints by local residents, the statue was removed from public view and returned to its owner. Evidently, Joy was considered a reminder of the community's 'bad old days', when it was better known for prostitution than restaurants. In a nation in which almost every sizable community has proudly erected monuments to military men, the removal of Joy reveals much about labour and gender relations in Australia. For Frances, the removal of Joy is symbolic, our historical treatment of sex workers having parallels with our treatment of the convicts. This work sets out to give these women (male prostitutes do not figure in this history) a voice and break with the stereotypes of 'abandoned whores' or 'sad victims'. It also sets out to place the sex industry in the broader national and international context in which it has historically operated...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Red light cameras were introduced in Victoria in August 1983, with the intention of reducing the number of accidents that result from motorists disobeying red traffic signals at signalised intersections. Accident data from 46 treated and 46 control sites from 1981 to 1986 were analysed. The analysis indicated that red light camera use resulted in a reduction in the incidence of right angle accidents, and in the number of accident casualties. Legislation was introduced in March 1986 to place the onus for red light camera offences onto the vehicle owner. This legislation was intended to improve Police efficiency and therefore increase the number of red light cameras in operation. Data supplied by the Police indicated that these aims have beneficial road safety effects.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

NMR studies of methyldichlorophosphine have been undertaken in the nematic phase of mixed liquid crystals of opposite diamagnetic anisotropies. The rα structure is derived. The proton chemical-shift anisotropy has been determined from the studies without the use of a reference compound and without a change of experimental conditions. It is shown that the molecule orients in the liquid crystal with positive diamagnetic anisotropy in such a way that the C3 symmetry axis of the CH3P moiety is preferentially aligned perpendicular to the direction of the magnetic field, unlike other similar systems. This is interpreted in terms of the formation of a weak solvent-solute molecular complex. The heteronuclear indirect spin-spin coupling constants are determined. The sign of the two-bond JPH is found to be positive.