15 resultados para Spraying and dusting residues in agriculture

em Deakin Research Online - Australia


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The southern bent-wing bat (Miniopterus schreibersii bassanii) is an insectivorous, obligate cave dwelling species found in south-eastern South Australia and western Victoria, Australia. In recent times, the finger of blame for an apparent population decline at Bat Cave, Naracoorte (one of only two known maternity roosts for this species, the other being Starlight Cave, Warrnambool) has been pointed at pesticide use in the region, following the finding of organochlorine and organophosphate insecticide residues in bat guano. This study sampled juvenile southern bent-wing bats from Bat Cave and Starlight Cave, and determined DDT, DDD and DDE concentrations in liver, pectoral muscle, brain and back-depot fat tissues.

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In recent times, the apparent population decline of the southern bent-wing bat (Miniopterus schreibersii bassanii) at Bat Cave, Naracoorte has been ascribed to pesticide use in the region, following the finding of organochlorine and orgaonophosphate insecticide residues in bat guano. Adult southern bent-wing bats were collected from Bat Cave and Starlight Cave in 2003. Organochlorine contaminants were detected in all carcass samples: p,p′-DDE was by far the most dominant contaminant with concentrations ranging from 11 000 to 59 000 ng g&minus;1, followed by p,p′-DDT (110–1600 ng g&minus;1), p,p′-DDD (35–620 ng g&minus;1), ∑PCBs (33–490 ng g&minus;1), ∑chlordane and related compounds (7.9–270 ng g&minus;1), HCB (1.6–120 ng g&minus;1), HP epox. (3.1–230 ng g&minus;1), TCPMOH (3.8–38 ng g&minus;1), ∑HCHs (1.4–9.6 ng g&minus;1), and TCPMe (0.1–4.2 ng g&minus;1) (all values on lipid-weight basis). No significant difference in DDE, DDD, DDT, ∑DDT, ∑PCB, trans-chlordane, heptachlor epoxide, trans-nonachlor, α-HCH, β-HCH, γ-HCH, TCPMOH or TCPMe concentrations were observed either between sexes within sites, or between sites (p > 0.05). However, there were significant differences in HCB and oxychlordane concentrations between sexes and between sites (p < 0.05), between site differences in cis-nonachlor concentrations in male bats (p < 0.05), and cis-chlordane concentrations between sexes at Starlight Cave, and between males of each site (p < 0.05). There were also significant differences in the liver concentrations of some metals between sexes within sites (Ag, Cd, Co, Cu, Pb, Se, Zn), and between sites (Ag, Cd, Co, Cu, Hg, Pb, Se, V, Zn). Clustering or grouping of sites was observed when the OC data was expressed on a lipid-weight basis. These inter-site differences in OC concentrations reflect local exposure over a period of time, and do not unambiguously support any suggestion that we are witnessing incipient speciation. However, for conservation purposes, it may be prudent to assume that there are two sub-populations of M. s. bassani feeding in different locations in this region of southern Australia, rather than the single homogeneous population suggested by genetic studies.

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Granulocyte colony-stimulating factor (G-CSF) is the major regulator of granulopoiesis and acts through binding to its specific receptor (G-CSF-R) on neutrophilic granulocytes. Previous studies of signaling from the 4 G-CSF-R cytoplasmic tyrosine residues used model cell lines that may have idiosyncratic, nonphysiological responses. This study aimed to identify specific signals transmitted by the receptor tyrosine residues in primary myeloid cells. To bypass the presence of endogenous G-CSF-R, a chimeric receptor containing the extracellular domain of the epidermal growth factor receptor in place of the entire extracellular domain of the G-CSF-R was used. A series of chimeric receptors containing tyrosine mutations to phenylalanine, either individually or collectively, was constructed and expressed in primary bone marrow cells from G-CSF-deficient mice. Proliferation and differentiation responses of receptor-expressing bone marrow cells stimulated by epidermal growth factor were measured. An increased 50% effective concentration to stimulus of the receptor Ynull mutant indicated that specific signals from tyrosine residues were required for cell proliferation, particularly at low concentrations of stimulus. Impaired responses by mutant receptors implicated G-CSF-R Y764 in cell proliferation and Y729 in granulocyte differentiation signaling. In addition, different sensitivities to ligand stimulation between mutant receptors indicated that G-CSF-R Y744 and possibly Y729 have an inhibitory role in cell proliferation. STAT activation was not affected by tyrosine mutations, whereas ERK activation appeared to depend, at least in part, on Y764. These observations have suggested novel roles for the G-CSF-R tyrosine residues in primary cells that were not observed previously in studies in cell lines.

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The so-called ‘biotechnology clause’ of Article 27.3(b) of the WTO-TRIPS Agreement requires from member states protection for plant varieties either via the patent system or via an ‘effective sui generis system’ or by a combination of the two. Many developing countries prefer forms of sui generis protection, which allow them to include exceptions and protection measures for traditional agricultural practices and the traditional knowledge of farmers and local communities. However, ‘traditional knowledge’ remains a vaguely defined term. Its extension to biodiversity has brought a diffusion of the previously clearer link between protected subject matter, intellectual property and potential beneficiaries. The Philippine legislation attempts a ‘bottom-up’ approach focusing on the holistic perceptions of indigenous communities, whereas national economic interests thus far receive priority in India’s more centralist approach. Administrative decentralisation, recognition of customary rights, disclosure requirements, registers of landraces and geographical indications are discussed as additional measures, but their implementation is equally challenging. The article concludes that many of the concepts remain contested and that governments have to balance the new commercial incentives with the biodiversity considerations that led to their introduction, so that the system can be made sufficiently attractive for both knowledge holders and potential users of the knowledge.

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Efforts to increase fruit and vegetable consump­tion are a significant aspect of national approaches to preventive health. However, policy frameworks for increasing fruit and vegetable consumption rarely take an integrated food-systems approach that includes a focus on production. In this policy analysis and commentary we examine fruit and vegetable production in peri-urban areas of Melbourne in Victoria, Australia, and highlight the significance of emerging environmental and eco­nomic pressures on fruit and vegetable production. This examination will be of interest to other locations around the world also experiencing pressure on their peri-urban agriculture. These pressures suggest that the availability and afforda­bility of fruit and vegetable supplies cannot be taken for granted, and that future initiatives to increase fruit and vegetable consumption should include a focus on sustainable production. Threats to production that include environmental pressures, together with the loss and cost of peri-urban agri­cultural land and a cost-price squeeze due to rising input costs and low farm-gate prices, act in combi­nation to threaten the viability of the Victorian fruit and vegetable industries. We pro­pose that policy initiatives to increase fruit and vegetable consumption should include measures to address the pressures facing production, and that the most effective policy responses are likely to be integrated approaches that aim to increase fruit and vegetable availability and affordability through innovative solutions to problems of production and distribu­tion. Some brief examples of potential integrated policy solutions are identified to illu­strate the possibilities and stimulate discussion.

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Complementary DNA (cDNA) encoding Bufo marinus (toad) preproatrial natriuretic peptide (preproANP) was isolated by reverse-transcription polymerase chain reaction. Sequence analysis of toad preproANP cDNA revealed an open reading frame of 150 amino acid residues, which shared 72% and 66% identity with Rana catesbeiana and Xenopus laevis preproANP, respectively. The deduced amino acid sequence of toad ANP that corresponded to ANP 1–24 of R. catesbeiana and Rana ridibunda was identical, but it differed by four residues from that of X. laevis. ANP mRNA transcripts were also shown to be expressed in the toad kidney. Subsequently, the effect of frog ANP (1–24) on renal function in toad was examined using a perfused kidney preparation. The arterial infusion of frog ANP caused a dose-dependent decrease in the arterial perfusion pressure that was associated with an increase in the glomerular filtration rate (GFR) and a renal natriuresis and diuresis. The renal natriuresis and diuresis resulted predominantly from an increased GFR rather than from direct tubular effects. This study demonstrates that ANP can regulate renal function, which suggests it may be involved in overall fluid volume regulation.

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The River Murray, Australia, is a highly regulated river from which almost 80% of mean annual flow is removed for human use, primarily irrigated agriculture. Consequent changes to the pattern and volume of river flow are reflected in floodplain hydrology and, therefore, the wetting/drying patterns of floodplain wetlands. To explore the significance of these changes, macroinvertebrate samples were compared between permanent and temporary wetlands following experimental flooding in a forested floodplain of the River Murray. Weekly samples from two permanent wetlands and four associated temporary sites were used to track changes in macroinvertebrate assemblage composition. Non-metric multidimensional scaling was used to ordinate the macroinvertebrate data, indicating consistent differences between the biota of permanent and temporary wetlands and between the initial and later assemblages in the temporary sites. There were marked changes over time, but little sign that the permanent and temporary assemblages were becoming more alike over the 25-week observation period. The apparent heterogeneity of these systems is of particular importance in developing river management plans which are likely to change flooding patterns. Such plans need to maintain a mosaic of wetland habitats if floodplain biodiversity is to be supported.

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The last few years have seen the identification of numerous small molecules that selectively inhibit specific class I isoforms of PI3K (phosphoinositide 3-kinase), yet little has been revealed about the molecular basis for the observed selectivities. Using site-directed mutagenesis, we have investigated one of the areas postulated as being critical to the observed selectivity. The residues Thr886 and Lys890 of the PI3Kγ isoform project towards the ATP-binding pocket at the entrance to the catalytic site, but are not conserved. We have made reciprocal mutations between those residues in the β isoform (Glu858 and Asp862) and those in the α isoform (His855 and Gln859) and evaluated the potency of a range of reported PI3K inhibitors. The results show that the potencies of β-selective inhibitors TGX221 and TGX286 are unaffected by this change. In contrast, close analogues of these compounds, particularly the α-isoform-selective compound (III), are markedly influenced by the point mutations. The collected data suggests two distinct binding poses for these inhibitor classes, one of which is associated with potent PI3Kβ activity and is not associated with the mutated residues, and a second that, in accord with earlier hypotheses, does involve this pair of non-conserved amino acids at the catalytic site entrance and contributes to the α-isoform-selectivity of the compounds studied.

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This paper reports some of the findings from a project that aimed to identify effective processes for ensuring that the content of learning activities is relevant to the changing needs of clients, and evolves so as to always incorporate the best available knowledge and science. This paper focuses on findings relating to the drivers for the development of new or substantially revised learning programs. The project, ‘Providing client-focussed education and training’, was funded by the FarmBis section of the Department of Agriculture, Fisheries and Forestry. The project also produced a self-assessment checklist for training providers to identify ways of improving the development and delivery of training. The key issues include continuous monitoring of client’s needs, and actively seeking opportunities to meet and work with industry organisations, other training providers and funding bodies.

There appear to be two drivers for the development of learning programs. One is problems or opportunities identified by people and organisations that could be termed ‘scanners’ and who tend not to be potential participants, the other is learning needs expressed by individuals or enterprises who want to participate in learning activities.

Scanners are typically industry organisations, government agencies and researchers, but may include providers and participants. Scanners identify learning needs that are not yet being expressed by potential participants, with the occasional exception of leading primary producers. Expressed participant needs drive the development of other programs. Providers become aware of the need for a new or substantially revised program, for example as a result of feedback from an existing program, because of legislative change or from delivering a similar program in other industries or contexts (for example computer training). Brokers (such as industry organisations who work to connect providers and participants) and ‘champions’ of training help participants identify and articulate their learning needs.

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Social capital helps communities respond positively to change. Research in agricultural businesses and into managing change through learning in communities has highlighted the importance of relationships between people and the formal and informal infrastructure of communities to the quality of outcomes experienced by communities, businesses and individuals. Communities can be geographic communities - the data drawn on in this paper are from an island community, for example or communities-of-common-purpose, such as agricultural organisations. This paper reviews research into managing change through learning and social capital, presents a model of the simultaneous building and use of social capital and explores the ways in which learning as part of an agricultural community can be used to bring benefits to geographic communities such as islands. The model presented in this paper stems from studies of the informal learning process that builds resilient communities. It conceptualises the way in which social capital is used and built in interactions between individuals. There are two stages to the model. The first stage depicts social capital at the micro level of one-on-one interactions where it is built and used. The second stage of the model is about the interrelationship of micro-level social capital processes with the community and societal-level social capital resources.

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Street Art: Mirror Reflections on urban AgricultureThis chapter will look at the way socio-political commentary exists in street art and how it has tended in recent times to be displayed overlooking community urban gardens. The urgency with which inner suburban councils in Melbourne Australia have dedicated themselves to carving out recreational spaces is a reflection on the expectations of multi-cultural groups whose culture incorporates the growth of vegetable and fruits close to their place of residence. Street art, famous for its commentary on urban ugliness, has integrated its philosophy and aesthetics, along side notable community gardens in Melbourne. The images incorporate the aims of urban agriculture whilst often simultaneously critiquing the alienation of the urban dweller cut so relentlessly from the means of growing food and from accessing land that might produce it. Community gardens in the twenty-first century go some way to reversing a state of being in which ‘workers’ were alienated from the source of their labor and their survival. This chapter will also probe the extent to which street art in the inner laneways of Melbourne incorporate in to their designs fauna and flora. This reference to all that is organic in environments devoid of vegetation draws attention not only to that absence but also for the need to address it. This work will therefore deal with two interrelating themes: 1. Street art that complements community gardens; 2. Street art that engages with agricultural imagery and images of fauna and flora with the aim of subverting the continual growth of unregulated concrete jungles. The chapter will be informed by interviews with well known Australian street artists and will also explore the work they have done in Paris, Jamaica, London and Miami on both themes stipulated above.

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Gastrointestinal nematodes limit the growth, production and welfare of goats but there are few reliable sources of information for recommending management practices across flocks. The effects of animal species (Angora goat, Merino sheep, mixed-grazed goats and mixed-grazed sheep at the ratio of 1:1) and stocking rate (SR: 7.5, 10, 12.5 animals/ha) on gastrointestinal parasitism were determined in a replicated experiment on improved annual temperate pastures in southern Australia, from 1981 to 1984. Detailed monitoring of gastrointestinal nematodes was undertaken on animals before, during (five times per year) and at the conclusion of studies using faecal strongyle egg counts (WEC) and total worm counts. Sheep had a greater proportion of nematodes as Teladorsagia spp. and goats a greater incidence of Trichostrongylus spp. Both goats and sheep developed resistance to Nematodirus spp. during the experiment. WEC was similar in goats and sheep at the start of the experimental period but, thereafter, was consistently greater in goats than in sheep. While WEC was highly related to total worm count, the regressions for sheep and goats were different. Increasing the SR increased the WEC of goats and mixed-grazed goats but not of sheep. During the experiment, WEC declined at 7 and 10 animals/ha but increased at 12.5/ha. Mixed grazing with goats provided beneficial effects for sheep at all stocking rates, but the effects for goats were dependent on the stocking rate, being beneficial at 7.5 and 10/ha but harmful at 12.5/ha. The WEC of separately grazed goats were generally higher than the WEC of mixed grazed goats. The WEC of mixed sheep were lower than those of separately grazed sheep. During the experiment, the WEC of mixed grazed sheep declined faster than the WEC of separately grazed sheep but the WEC of separately grazed goats at 12.5/ha and of mixed grazed goats at 10 and 12.5/ha increased. Under the environmental and pastoral conditions examined, Angora wether goats should not be grazed at SR above those recommended for wether sheep. In the present study, the impact of gastrointestinal-nematode infections in goats was reduced at lower SR. Further, mixed grazing of Angora wether goats with wether sheep at or below the recommended SR resulted in reduced gastrointestinal parasitism for both sheep and goats, compared with monospecific grazing conditions. Goats did not represent a gastrointestinal-nematode hazard to sheep. © 2014 CSIRO.

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Australia's northern savannas are one of the few remaining large and mostly intact natural areas on Earth. However, their biodiversity and ecosystem values could be threatened if proposed agricultural development proceeds. Through land-use change scenarios, we explored trade-offs and synergies among biodiversity conservation, carbon farming and agriculture production in northern Australia. We found that if all suitable soils were converted to agriculture, habitat at unique recorded locations of three species would disappear and 40 species and vegetation communities could lose more than 50% of their current distributions. Yet, strategically considering agriculture and biodiversity outcomes leads to zoning options that could yield >56,000 km2 of agricultural development with a significantly lower impact on biodiversity values and carbon farming. Our analysis provides a template for policy-makers and planners to identify areas of conflict between competing land-uses, places to protect in advance of impacts, and planning options that balance agricultural and conservation needs.