876 resultados para McKenzie, Reggie
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The last two decades has seen a proliferation in the provision of, and importance attached to, coach education in many Western countries [1]. Pivotal to many coach education programmes is the notion of apprenticeship [2,3,4]. Increasingly, mentoring is being positioned as a possible tool for enhancing coach education and consequently professional expertise [5]. However, there is a paucity of empirical data on interventions in, and evaluations of, coach education programmes. In their recent evaluation of a coach education programme Cassidy, Potrac & McKenzie [6] conclude that the situated learning literature could provide coach educators with a generative platform for the (re)examinationof apprenticeships and mentoring in a coach education context. This paper consequently discusses the merits of using situated learning theory [7] and the associated concept of Communities of Practice (CoP) [8] to stimulate discussion on developing new understandings of the practices of apprenticeship and mentoring in coach education.
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Representation of Aborigines by Aborigines and non -Aborigines; articles by Andrew Dewdney, Mervyn Biship, Alana Harris, Sandy Edwards, Rea Saunders, Ricky Maynard , Brenda Croft, Ruth Braunstein, Michael Riley, Huw Davies, Penny Taylor, Darlene McKenzie, Kurt Brereton and Eric Michaels, annotated separately.
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Collecting has become a popular hobby within Western society, with collectables including anything from ‘bottle tops’ to ‘skyscrapers’. As the nature and size of these collections can impact upon the use of space in the home, the purpose of this study is to explore the relationship between the collections, space in the home and the impacts on others. This qualitative study explores the experiences of 11 Australian collectors, investigating the motivations, practices and adaption techniques used within their urban home environment. The themes of sentimentality, sociability and spatial tensions, including physical, personal and use of space are discussed within the context of their home and family environments. Overall the practice of collecting objects is a complex, varied, sentimental and sociable activity, providing enjoyment, knowledge and friendships. Space can be a central consideration to the practice of collecting as collections shape and are shaped by the available space in a household.
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Background The genetic mutation resulting in osteogenesis imperfecta (OI) type V was recently characterised as a single point mutation (c.-14C > T) in the 5' untranslated region (UTR) of IFITM5, a gene encoding a transmembrane protein with expression restricted to skeletal tissue. This mutation creates an alternative start codon and has been shown in a eukaryotic cell line to result in a longer variant of IFITM5, but its expression has not previously been demonstrated in bone from a patient with OI type V. Methods Sanger sequencing of the IFITM5 5' UTR was performed in our cohort of subjects with a clinical diagnosis of OI type V. Clinical data was collated from referring clinicians. RNA was extracted from a bone sample from one patient and Sanger sequenced to determine expression of wild-type and mutant IFITM5. Results: All nine subjects with OI type V were heterozygous for the c.-14C > T IFITM5 mutation. Clinically, there was heterogeneity in phenotype, particularly in the manifestation of bone fragility amongst subjects. Both wild-type and mutant IFITM5 mRNA transcripts were present in bone. Conclusions The c.-14C > T IFITM5 mutation does not result in an RNA-null allele but is expressed in bone. Individuals with identical mutations in IFITM5 have highly variable phenotypic expression, even within the same family.
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The study monitored the emissions of volatile organic compounds (VOCs) from the exhaust of cars fuelled by liquefied petroleum gas (LPG) and unleaded petrol (ULP). Six cars, four fuelled by LPG and two by ULP, were tested on a chassis dynamometer at two different cruising modes of operation (60 km h−1 and 80 km h−1) and idle. A total of 33 VOCs were identified in the exhaust of both types of fuels by the use of GC/MS. Due to the complexity of the dataset, Multi Criteria Decision Making (MCDM) software PROMETHEE and GAIA was used to rank the least polluting mode and fuel. The 60 km h−1 driving speed was identified as the cleaner mode of driving as was LPG fuel. The Ozone Formation Potential (OFP) of the VOCs was also calculated by using the incremental reactivity scale. Priority VOCs leading to ozone formation were identified according to the three incremental reactivity scales: MIR, MOIR and EBIR. PROMETHEE was applied to assess the most preferred scale of reactivity for predicting ozone formation potential under different scenarios. The results enhance the understanding of the environmental value of using LPG to power passenger cars.
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The loss and recovery of intertidal seagrass meadows were assessed following the flood related catastrophic loss of seagrass meadows in February 1999 in the Sandy Strait, Queensland. Region wide recovery rates of intertidal meadows following the catastrophic disturbance were assessed by mapping seagrass abundance in the northern Great Sandy Strait region prior to and on 3 occasions after widespread loss of seagrass. Meadow-scale assessments of seagrass loss and recovery focussed on two existing Zostera capricorni monitoring meadows in the region. Mapping surveys showed that approximately 90% of intertidal seagrasses in the northern Great Sandy Strait disappeared after the February 1999 flooding of the Mary River. Full recovery of all seagrass meadows took 3 years. At the two study sites (Urangan and Wanggoolba Creek) the onset of Z. capricorni germination following the loss of seagrass occurred 14 months post-flood at Wanggoolba Creek, and at Urangan it took 20 months for germination to occur. By February 2001 (24 months post-flood) seagrass abundance at Wanggoolba Creek sites was comparable to pre-flood abundance levels and full recovery at Urangan sites was complete in August 2001 (31 months post-flood). Reduced water quality characterised by 2–3 fold increases in turbidity and nutrient concentrations during the 6 months following the flood was followed by a 95% loss of seagrass meadows in the region. Reductions in available light due to increased flood associated turbidity in February 1999 were the likely cause of seagrass loss in the Great Sandy Strait region, southern Queensland. Although seasonal cues influence the germination of Z. capricorni, the temporal variation in the onset of seed germination between sites suggests that germination following seagrass loss may be dependent on other factors (eg. physical and chemical characteristics of sediments and water). Elevated dissolved nitrogen concentrations during 1999 at Wanggoolba Creek suggest that this site received higher loads of sediments and nutrients from flood waters than Urangan. The germination of seeds at Wanggoolba Creek one year prior to Urangan coincides with relatively low suspended sediment concentrations in Wanggoolba Creek waters. The absence of organic rich sediments at Urangan for many months following their removal during the 1999 flood may also have inhibited seed germination. Data from population cohort analyses and population growth rates showed that rhizome weight and rhizome elongation rates increased over time, consistent with rapid growth during increases in temperature and light availability from May to October
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In coastal waters and estuaries, seagrass meadows are often subject to light deprivation over short time scales (days to weeks) in response to increased turbidity from anthropogenic disturbances. Seagrasses may exhibit negative physiological responses to light deprivation and suffer stress, or tolerate such stresses through photo-adaptation of physiological processes allowing more efficient use of low light. Pulse Amplitude Modulated (PAM) fluorometery has been used to rapidly assess changes in photosynthetic responses along in situ gradients in light. In this study, however, light is experimentally manipulated in the field to examine the photosynthesis of Halophila ovalis and Zostera capricorni. We aimed to evaluate the tolerance of these seagrasses to short-term light reductions. The seagrasses were subject to four light treatments, 0, 5, 60, and 90% shading, for a period of 14 days. In both species, as shading increased the photosynthetic variables significantly (P < 0.05) decreased by up to 40% for maximum electron transport rates (ETRmax) and 70% for saturating irradiances (Ek). Photosynthetic efficiencies (a) and effective quantum yields (ΔF/Fm′ ) increased significantly (P < 0.05), in both species, for 90% shaded plants compared with 0% shaded plants. H. ovalis was more sensitive to 90% shading than Z. capricorni, showing greater reductions in ETR max, indicative of a reduced photosynthetic capacity. An increase in Ek, Fm′ and ΔF/Fm′ for H. ovalis and Z. capricorni under 90% shading suggested an increase in photochemical efficiency and a more efficient use of low-photon flux, consistent with photo-acclimation to shading. Similar responses were found along a depth gradient from 0 to10 m, where depth related changes in ETRmax and Ek in H. ovalis implied a strong difference of irradiance history between depths of 0 and 5-10 m. The results suggest that H. ovalis is more vulnerable to light deprivation than Z. capricorni and that H. ovalis, at depths of 5-10 m, would be more vulnerable to light deprivation than intertidal populations. Both species showed a strong degree of photo-adaptation to light manipulation that may enable them to tolerate and adapt to short-term reductions in light. These consistent responses to changes in light suggest that photosynthetic variables can be used to rapidly assess the status of seagrasses when subjected to sudden and prolonged periods of reduced light
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This study uses chlorophyll a fluorescence to examine the effect of environmentally relevant (1-4 h) exposures of thermal stress (35-45 [deg]C) on seagrass photosynthetic yield in seven tropical species of seagrasses. Acute response of each tropical seagrass species to thermal stress was characterised, and the capacity of each species to tolerate and recover from thermal stress was assessed. Two fundamental characteristics of heat stress were observed. The first effect was a decrease in photosynthetic yield (Fv / Fm) characterised by reductions in F and Fm'. The dramatic decline in Fv / Fm ratio, due to chronic inhibition of photosynthesis, indicates an intolerance of Halophila ovalis, Zostera capricorni and Syringodium isoetifolium to ecologically relevant exposures of thermal stress and structural alterations to the PhotoSystem II (PSII) reaction centres. The decline in Fm' represents heat-induced photoinhibition related to closure of PSII reaction centres and chloroplast dysfunction. The key finding was that Cymodocea rotundata, Cymodocea serrulata, Halodule uninervis and Thalassia hemprichii were more tolerant to thermal stress than H. ovalis, Z. capricorni and S. isoetifolium. After 3 days of 4 h temperature treatments ranging from 25 to 40 [deg]C, C. rotundata, C. serrulata and H. uninervis demonstrated a wide tolerance to temperature with no detrimental effect on Fv / Fm' qN or qP responses. These three species are restricted to subtropical and tropical waters and their tolerance to seawater temperatures up to 40 [deg]C is likely to be an adaptive response to high temperatures commonly occurring at low tides and peak solar irradiance. The results of temperature experiments suggest that the photosynthetic condition of all seagrass species tested are likely to suffer irreparable effects from short-term or episodic changes in seawater temperatures as high as 40-45 [deg]C. Acute stress responses of seagrasses to elevated seawater temperatures are consistent with observed reductions in above-ground biomass during a recent El Nino event.
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Seagrass meadows across north-eastern Australia, survive a range of environmental conditions in coastal bays, reefs, estuarine and deepwater habitats through adaptation of a range of structural, morphological and physiological features. The aim of this study was to investigate the influence of spatial features (habitat type, site and depth) and photon flux on the photosynthetic performance of 11 tropical seagrass species. Pulse amplitude modulated (PAM) fluorometry was used to generate rapid light curves from which measures of maximal electron transport rate (ETRmax), photosynthetic efficiency (?), saturating irradiance (Ek) and effective quantum yield (?F/Fm?) were derived. The amount of light absorbed by leaves (absorption factor) was also determined for each population. In intertidal habitats many seagrass species exhibited typical sun-type responses with a close coupling of both ETRmax and Ek with photon flux. Photosynthetic performance ranged from minima in Thalassodendron ciliatum to maxima in Syringodium isoetifolium. The absence of a coupling between photosynthetic performance and photon flux in subtidal populations was most likely due to highly variable light climates and possible light attenuation, and hence the photo-biology of estuarine and deepwater seagrasses exhibited photosynthetic responses indicative of light limitation. In contrast seagrass species from shallow reef and coastal habitats for the most part exhibited light saturation characteristics. Of all the variables examined ETRmax, Ek and ?F/Fm? were most responsive to changing light climates and provide reliable physiological indicators of real-time photosynthetic performance of tropical seagrasses under different light conditions.
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Objective: To provide a visual guide for oesophagogastric ulcer scoring and recognition of different morphological changes in the pars oesophagea. Design: Pig stomachs were collected at slaughter and visually evaluated and scored for parakeratosis, erosion and ulceration in the pars oesophagea. Results: A visual and descriptive guide is presented that will aid in the objective assessment and scoring of oesophagogastric ulceration in pigs within the pig health monitoring system (PHMS), namely to the four categories of 0 = normal stomach, 1 = parakeratosis and thickened epithelium, 2 = erosions and 3 = developed ulcers with and without stenosis. Conclusion: A visual guide has been developed that illustrates the full range of morphological changes that can occur in the pars oesophagea of the stomach within the few currently recognised stages of the disease.
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The distribution and nutritional profiles of sub-tidal seagrasses from the Torres Strait were surveyed and mapped across an area of 31,000 km2. Benthic sediment composition, water depth, seagrass species type and nutrients were sampled at 168 points selected in a stratified representative pattern. Eleven species of seagrass were present at 56 (33.3%) of the sample points. Halophila spinulosa, Halophila ovalis, Cymodocea serrulata and Syringodium isoetifolium were the most common species and these were nutrient profiled. Sub-tidal seagrass distribution (and associated seagrass nutrient concentrations) was generally confined to northern-central and south-western regions of the survey area (
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A dense population of Pimelea trichostachya plants (Family Thymelaeaceae) in pasture poisoned a horse herd in southern inland Queensland in October-November 2005. Plant density was 2 to 45 g wet weight/m2 (mean 16 g/m2) from 5 to 69 plants/m2 (mean 38 plants/m2) representing 3 to 20% (mean 9%) of the volume of pasture on offer. Ten of 35 mares, fillies and geldings were affected. Clinical signs were loss of body weight, profound lethargy, serous nasal discharge, severe watery diarrhoea and subcutaneous oedema of the intermandibular space, chest and ventral midline. Pathological findings were anaemia, leucocytopenia, hypoproteinaemia, dilatation of the right ventricle of the heart, dilated hepatic portal veins and periportal hepatic sinusoids (peliosis hepatis), alimentary mucosal hyperaemia and oedema of mesenteric lymph nodes. Cattle grazing the same pasture were affected by Pimelea poisoning simultaneously. Removal of the horses to Pimelea-free pasture initiated recovery. The one other incident of this syndrome, previously only recognised in cattle in Australia, occurred in horses, in South Australia in 2002, with access to a dense Pimelea simplex population.
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The report of Brunfelsia poisoning of dogs in Sydney by Drs Singh, Cowan and Child is very welcome, but it raises one important scientific point that has been further highlighted by the letter from Dr Seavers. Neither in the case report nor in Dr Seavers' letter is the species or cultivar of the plants identified. There are about 40 known Brunfelsia species, a number of which are cultivated in tropical to temperate climate gardens in Australia. It is noteworthy that Dr Seavers speculates about the Brunfelsia plants involved in dog poisonings in Australia, suggesting that 'dwarf' plants may be more poisonous ...
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Involvement in scientifically structured habitat monitoring is a relatively new concept to the peoples of Torres Strait. The approach we used was to focus on awareness, and to build the capacity of groups to participate using Seagrass-Watch as the vehicle to provide education and training in monitoring marine ecosystems. The project successfully delivered quality scientifically rigorous baseline information on the seasonality of seagrasses in the Torres Strait-a first for this region. Eight seagrass species were identified across the monitoring sites. Seagrass cover varied within and between years. Preliminary evidence indicated that drivers for seagrass variability were climate related. Generally, seagrass abundance increased during the north-west monsoon (Kuki), possibly a consequence of elevated nutrients, lower tidal exposure times, less wind, and higher air temperatures. Low seagrass abundance coincided with the presence of greater winds and longer periods of exposure at low tides during the south-east trade wind season (Sager). No seasonal patterns were apparent when frequency of disturbance from high sedimentation and human impacts was high. Seagrass-Watch has been incorporated in to the Thursday Island High School's Marine Studies Unit ensuring continuity of monitoring. The students, teachers, and other interested individuals involved in Seagrass-Watch have mastered the necessary scientific procedures to monitor seagrass meadows, and developed skills in coordinating a monitoring program and skills in mentoring younger students. This has increased the participants' self-esteem and confidence, and given them an insight into how they may participate in the future management of their sea country.
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A 300-strong Angus-Brahman cattle herd near Springsure, central Queensland, was being fed Acacia shirleyi (lancewood) browse during drought and crossed a 5-hectare, previously burnt area with an almost pure growth of Dysphania glomulifera subspecies glomulifera (red crumbweed) on their way to drinking water. Forty cows died of cyanide poisoning over 2 days before further access to the plant was prevented. A digital image of a plant specimen made on a flat-bed scanner and transmitted by email was used to identify D glomulifera. Specific advice on the plant's poisonous properties and management of the case was then provided by email within 2 hours of an initial telephone call by the field veterinarian to the laboratory some 600 km away. The conventional method using physical transport of a pressed dried plant specimen to confirm the identification took 5 days. D glomulifera was identified in the rumen of one of two cows necropsied. The cyanogenic potential of D glomulifera measured 4 days after collection from the site of cattle deaths was 18,600 mg HCN/kg in dry matter. The lethal dose of D glomulifera for a 420 kg cow was estimated as 150 to 190 g wet weight. The plant also contained 4.8% KNO3 equivalent in dry matter, but nitrate-nitrite poisoning was not involved in the deaths.