Backpackers and sustainable tourism : exploring the potential

There is conflicting evidence in the literature with respect to backpackers as contributors to sustainable travel. This paper explores this market with respect to sustainable travel attitudes, behaviours and preferences. More specifically it examined the motivations of backpacker visitors to Australia, their preferences for environmentally friendly and volunteer tourism experiences, and explored attitudes towards the influence of environmental impacts on the future of travel. The resultsindicate that not all backpackers necessarily have a strong focus on the sustainability of their travel, but that those interested in community and environmental volunteering have the greatest potential to make meaningful contributions.

Porphyrin containing isoindoline nitroxides as potential fluorescence sensors of free radicals

A series of new spin-labeled porphyrin containing isoindoline nitroxide moieties were synthesized and characterized as potential free radical fluorescence sensors. Fluorescence-suppression was observed in the free-base monoradical porphyrins, whilst the free-base biradical porphyrins exhibited highly suppressed fluorescence about three times greater than the monoradical porphyrins. The observed fluorescence-suppression was attributed to enhanced intersystem crossing resulting from electronexchange between the doublet nitroxide and the excited porphyrin fluorophore. Notably, fluorescencesuppression was not as strong in the related metalated porphyrins, possibly due to insufficient spin coupling between the nitroxide and the porphyrin. Continuous wave EPR spectroscopy of the diradical porphyrins in fluid solution suggests that the nitroxyl-nitroxyl interspin distance is long enough and tumbling is fast enough not to detect dipolar coupling.

Edaravone containing isoindoline nitroxides for the potential treatment of cardiovascular ischaemia

A novel antioxidant for the potential treatment of ischaemia was designed by incorporating an isoindoline nitroxide into the framework of the free radical scavenger edaravone. 5-(3-Methyl-pyrazol-5-ol-1-yl)-1,1,3,3-tetramethylisoindolin-2-yloxyl 7 was prepared by N-arylation of 3-methyl-5-pyrazolone with 5-iodo-1,1,3,3-tetramethylisoindoline-2-yloxyl 8 in the presence of catalytic copper(I)iodide. Evaluation of 7, its methoxyamine derivative 10 and 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl (CTMIO) against edaravone 1 in ischaemic rat atrial cardiomyocytes revealed significant decreases in cell death after prolonged ischaemia for each agent; however the protective effect of the novel antioxidant 7 (showing greater than 85% reduction in cell death at 100 μM) was significantly enhanced over that of edaravone 1 alone. Furthermore, the activity for 7 was found to be equal to or greater than the potent cardioprotective agent N6-cyclopentyladenosine (CPA). The methoxyamine adduct 10 and edaravone 1 showed no difference between the extent of reduction in cell death whilst CTMIO had only a modest protective effect.

A new control-volume finite-element scheme for heterogeneous porous media : application to the drying of softwood

An improved mesoscopic model is presented for simulating the drying of porous media. The aim of this model is to account for two scales simultaneously: the scale of the whole product and the scale of the heterogeneities of the porous medium. The innovation of this method is the utilization of a new mass-conservative scheme based on the Control-Volume Finite-Element (CV-FE) method that partitions the moisture content field over the individual sub-control volumes surrounding each node within the mesh. Although the new formulation has potential for application across a wide range of transport processes in heterogeneous porous media, the focus here is on applying the model to the drying of small sections of softwood consisting of several growth rings. The results conclude that, when compared to a previously published scheme, only the new mass-conservative formulation correctly captures the true moisture content evolution in the earlywood and latewood components of the growth rings during drying.