890 research outputs found

    Regional tourist destinations - the role of information and communications technology (ICT) in collaboration amongst tourism providers

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    The tourism industry can be seen as one of the first business sectors where business functions are almost exclusively using information and communications technologies (ICT). This has impacted on the way in which regional tourism destinations are promoted. The method of promoting regions via the development of regional tourist destination websites or portals using Internet technologies is increasingly being adopted both in Australia and around the world. This paper investigates whether this approach is the most effective to achieve increased awareness and subsequent visitation of a region. Are there other ways to achieve a similar outcome? One such alternative is via a bottom up approach achieved through co-opetition or collaboration established within the group of local tourism industry operators. This cooperative networking is made possible via the use of ICT to facilitate the establishment of virtual business networks amongst tourism operators in a local community, cascading into an informal secondary tourism network within that region. In many Australian regional areas the tourism bureau has been the key node for local tourism, but this structure has been fraught with many problems. Little is known about their effectiveness in delivering services to local small and medium tourism enterprises (SMTEs). The role of tourism bureaus in local tourism networks is changing and a study of this dynamic is provided here as an example of the interaction between top down and bottom up approaches. Published case studies from around the world are considered demonstrating alternative approaches to using ICT to promote a region and communicate with potential visitors. Future empirical research is required to more fully understand the effectiveness of the different approaches

    Frog foams and natural protein surfactants

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    Foams and surfactants are relatively rare in biology because of their potential to harm cell membranes and other delicate tissues. However, in recent work we have identified and characterized a number of natural surfactant proteins found in the foam nests of tropical frogs and other unusual sources. These proteins, and their associated foams, are relatively stable and bio-compatible, but with intriguing molecular structures that reveal a new class of surfactant activity. Here we review the structures and functional mechanisms of some of these proteins as revealed by experiments involving a range of biophysical and biochemical techniques, with additional mechanistic support coming from more recent site-directed mutagenesis studies

    Aqueous solubilization of C60 fullerene by natural protein surfactants, latherin and ranaspumin-2

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    C60 fullerene is not soluble in water and dispersion usually requires organic solvents, sonication or vigorous mechanical mixing. However, we show here that mixing of pristine C60 in water with natural surfactant proteins latherin and ranaspumin-2 (Rsn-2) at low concentrations yields stable aqueous dispersions with spectroscopic properties similar to those previously obtained by more vigorous methods. Particle sizes are significantly smaller than those achieved by mechanical dispersion alone, and concentrations are compatible with clusters approximating 1:1 protein:C60 stoichiometry. These proteins can also be adsorbed onto more intractable carbon nanotubes. This promises to be a convenient way to interface a range of hydrophobic nanoparticles and related materials with biological macromolecules, with potential to exploit the versatility of recombinant protein engineering in the development of nano-bio interface devices. It also has potential consequences for toxicological aspects of these and similar nanoparticles

    Resonance assignments for latherin, a natural surfactant protein from horse sweat

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    Latherin is an intrinsically surfactant protein of ~23 kDa found in the sweat and saliva of horses. Its function is probably to enhance the translocation of sweat water from the skin to the surface of the pelt for evaporative cooling. Its role in saliva may be to enhance the wetting, softening and maceration of the dry, fibrous food for which equines are adapted. Latherin is unusual in its relatively high content of aliphatic amino acids (~25 % leucines) that might contribute to its surfactant properties. Latherin is related to the palate, lung, and nasal epithelium carcinoma-associated proteins (PLUNCs) of mammals, at least one of which is now known to exhibit similar surfactant activity to latherin. No structures of any PLUNC protein are currently available. 15N,13C-labelled recombinant latherin was produced in Escherichia coli, and essentially all of the resonances were assigned despite the signal overlap due to the preponderance of leucines. The most notable exceptions include a number of residues located in an apparently dynamic loop region between residues 145 and 154. The assignments have been deposited with BMRB accession number 19067

    Hydrophobic Ligand Binding by Zn-α_2-glycoprotein, a Soluble Fat-depleting Factor Related to Major Histocompatibility Complex Proteins

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    Zn-alpha2-glycoprotein (ZAG) is a member of the major histocompatibility complex (MHC) class I family of proteins and is identical in amino acid sequence to a tumor-derived lipid-mobilizing factor associated with cachexia in cancer patients. ZAG is present in plasma and other body fluids, and its natural function, like leptin's, probably lies in lipid store homeostasis. X-ray crystallography has revealed an open groove between the helices of ZAG's alpha1 and alpha2 domains, containing an unidentified small ligand in a position similar to that of peptides in MHC proteins (Sanchez, L. M., Chirino, A. J., and Bjorkman, P. J. (1999) Science 283, 1914-1919). Here we show, using serum-derived and bacterial recombinant protein, that ZAG binds the fluorophore-tagged fatty acid 11-(dansylamino)undecanoic acid (DAUDA) and, by competition, natural fatty acids such as arachidonic, linolenic, eicosapentaenoic, and docosahexaenoic acids. Other MHC class I-related proteins (FcRn, HFE, HLA-Cw*0702) showed no such evidence of binding. Fluorescence and isothermal calorimetry analysis showed that ZAG binds DAUDA with Kd in the micromolar range, and differential scanning calorimetry showed that ligand binding increases the thermal stability of the protein. Addition of fatty acids to ZAG alters its intrinsic (tryptophan) fluorescence emission spectrum, providing a strong indication that ligand binds in the expected position close to a cluster of exposed tryptophan side chains in the groove. This study therefore shows that ZAG binds small hydrophobic ligands, that the natural ligand may be a polyunsaturated fatty acid, and provides a fluorescence-based method for investigating ZAG-ligand interactions

    Samphire for waterlogged salt land

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    For non-waterlogged and mildly waterlogged salt land a number of salt-tolerant shrubs may be used for forage production. Areas which are highly saline and regularly waterlogged are not suited to these shrubs. However, during trials with shrub species, samphires (Arthrocnemum spp.) were found to volunteer and grow well on these sites. Research into the use of samphires has shown that it is possible to harvest seed and obtain a seed sample suitable for sowing through a drill. Established samphire stands provide useful grazing in many parts of the Western Australian wheatbelt

    The structure of latherin, a surfactant allergen protein from horse sweat and saliva

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    Latherin is a highly surface-active allergen protein found in the sweat and saliva of horses and other equids. Its surfactant activity is intrinsic to the protein in its native form, and is manifest without associated lipids or glycosylation. Latherin probably functions as a wetting agent in evaporative cooling in horses, but it may also assist in mastication of fibrous food as well as inhibition of microbial biofilms. It is a member of the PLUNC family of proteins abundant in the oral cavity and saliva of mammals, one of which has also been shown to be a surfactant and capable of disrupting microbial biofilms. How these proteins work as surfactants while remaining soluble and cell membrane-compatible is not known. Nor have their structures previously been reported. We have used protein nuclear magnetic resonance spectroscopy to determine the conformation and dynamics of latherin in aqueous solution. The protein is a monomer in solution with a slightly curved cylindrical structure exhibiting a ‘super-roll’ motif comprising a four-stranded anti-parallel β-sheet and two opposing α-helices which twist along the long axis of the cylinder. One end of the molecule has prominent, flexible loops that contain a number of apolar amino acid side chains. This, together with previous biophysical observations, leads us to a plausible mechanism for surfactant activity in which the molecule is first localized to the non-polar interface via these loops, and then unfolds and flattens to expose its hydrophobic interior to the air or non-polar surface. Intrinsically surface-active proteins are relatively rare in nature, and this is the first structure of such a protein from mammals to be reported. Both its conformation and proposed method of action are different from other, non-mammalian surfactant proteins investigated so far

    The Importance of Transport in Business’ Location Decisions -Scoping Study (Final Report)

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    The aim of this project was to review current literature of issues considered by businesses in choosing where they locate / relocate and in particular, the significance and importance to which transport is a factor within that decision-making process. The review pulled together the evidence already available about the factors which influence these decisions, the extent to which transport is a consideration within these decisions and the impacts of these decisions on the travel patterns of customers and staff, as well as operational considerations. From this review, the current evidence base was mapped out, identifying and prioritising the needs for future research in this area. This scoping study was needed to consolidate the level of understanding of the impact of transport in businesses' locational decision-making processes and to assist the Department in developing meaningful, evidence-based areas for future research, minimising the burden of research surveys on business respondents
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