56 resultados para Distribution of NTM

em Deakin Research Online - Australia


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Fallen timber is an important habitat resource for small vertebrate and invertebrate animals in forests. This exploratory study investigated the pattern of distribution of fallen timber (here termed 'logs') in a dry sclerophyll forest in the Brisbane Ranges, Victoria, by sampling transects located in
gully, mid-slope and ridge positions, at each of 10 sites. Gullies supported a significantly higher density and volume of logs than ridges. The lowest abundance of logs was on ridges. The mean volume of logs was 98.6 m3/ha for gullies, 38.5 m3/ha at mid-slope positions and 13.1 m3/ha for ridges. The
volume of logs at transects was significantly positively correlated with the density of larger trees (diameter >40 em). A number of animal species in the Brisbane Ranges potentially use logs as a resource for shelter, foraging or perching, and hence the retention ofwoody debris will aid in habitat
management. The uneven distribution of logs in relation to forest topography and the size strueture of trees suggests that gullies, and forest stands with many large trees, are likely to be important habitats for species that use fallen timber. (The Victorian Naturalist 120 (2), 2003, 55-60)

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Previously, minimal work has been carried out on conulariids due to their rare occurrences and resultant biostratigraphical limitations. The palaeobiogeographical distribution of Permian conulariids suggests that they have a marked preference for cold to cool-water regions, that they are significant indicators for migration patterns, and that they can potentially provide information on the palaeogeographical configuration and movement of terranes. Permian conulariids are found in Australia, India, New Zealand, Pakistan, Iran, Afghanistan, Kashmir, China, Japan, Russia, Germany, Canada, United States of America, and Bolivia. The diversity of Permian conulariids is markedly higher in the polar regions than in the palaeoequatorial region.

Permian conulariid genera include Notoconularia Thomas 1969, Gondaconularia Waterhouse 1986, Cheliconularia Waterhouse 1986, Neoconularia Sugiyama 1942, Calloconularia Sinclair 1952, Diconularia Sinclair 1952, Paraconularia Sinclair 1940, Mesoconularia Boucek 1939 and Conularia Sowerby 1821. This paper describes two new species of conulariids: Diconularia meadepeakensis sp. nov. from the Phosphoria Formation (Guadalupian), Idaho, USA and Paraconularia kazanensis sp. nov. from the Sokian Horizon (?Roadian), Volga Region, Russia.

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The extent of disease caused by Phytophthora cinnamomi was determined within vegetation communities of Wilsons Promontory National Park. Aerial survey of visible symptoms by helicopter and systematic survey along all roads and tracks followed by isolation of the pathogen from soil found that in total 551 ha of moist foothill forest, heath and heathy woodland broad vegetation types were affected by the disease. P. cinnamomi was isolated from 93% of sites that, based on the presence of visible symptoms, were expected to yield the pathogen. The species-rich heathy woodland was most affected with 6.5% of the total area of this type showing symptoms of disease. The size of infestation ranged from 229 ha on the slopes of the Vereker Range in the north to less than 1 ha along the Sealers Cove Walking Track in the south. The potential for disease to spread into uninfested vegetation was estimated for all sites from which P. cinnamomi was isolated. Eight of 18 sites where evidence of disease was found were estimated to have a high potential for further disease spread. This study indicates that even though the disease may be waning in some areas of the Park, the pathogen is active and easily isolated from others and provides a continuing threat to susceptible vegetation communities.

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A model of a yam package is established for a ring spinning system. The yarn layer, surface area, and mass of the yam package are formulated with respect to the diameters of the empty bobbin and full yarn package, yarn count, and yarn winding-on time. Based on the principles of dynamics and aerodynamics, models of the power requirements for overcoming the skin friction drag, increasing the kinetic energy of the yarn package (bobbin and wound yarn), and overcoming the yarn wind-on tension are developed. The skin friction coefficient on the surface of a rotating yam package is obtained from experiment. The power distribution during yam packaging is discussed based on a case study. The results indicate that overcoming the skin friction drag during yarn winding consumes the largest amount of energy. The energy required to overcome the yarn wind-on tension is also significant.

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The Beautiful Firetail (Stagonopleura bella) is an uncommon, granivorous finch from coastal south-eastern Australia, with a distribution extending from mid-coastal New South Wales to south-eastern South Australia, including Tasmania. This paper presents a quantitative assessment of habitat use by the Beautiful Firetail based on data collected from 30 paired riparian and non-riparian sites in the foothill forests of the Victorian Highlands, Australia. The Beautiful Firetail occurred in two of the three forest blocks surveyed and was found almost exclusively at riparian sites. The Beautiful Firetail was most likely to occur at riparian sites on the coastal fall of the ranges at sites with high sedge cover and low cover of shrubs and bare ground. The species occurred at low densities (0.10–0.19 individuals ha–1) throughout the year. Records from the Atlas of Victorian Wildlife were used to describe the distribution of Beautiful Firetails in Victoria. Notable observations inland of the Great Dividing Range were recorded during the present study. Further study is required to understand the ecological requirements of the Beautiful Firetail throughout its range.


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In this article I challenge the claim that nuclearity is a central principle in the organization of texts. I propose the Framework for the Relational Analysis of Texts (FARS) which accounts for the paratactic and hypotactic realization of coherence relations. Within this framework, the taxis of coherence relations is co-textually dictated. I consider the writer choices in the distribution of discoursal salience and the intertextual and intercultural variation of these choices. It is suggested that divergence between approaches that perceive text as exhibiting both hypotactic and paratactic organization and those that see nuclearity as a basic characteristic of text structure arises from differences in the linguistic corpora examined during the construction of respective theoretical frameworks.

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Mapping and analysis of the distribution of environmental weeds is an important component of strategic weed management. Such information is particularly important in managing 'native invaders', where invasion characteristics must be clearly understood prior to any management action being taken. This paper reports on an investigation of the current distribution of the native invader Acacia longifolia ssp. sophorae (Labill.) Court (coast wattle) in south-west Victoria, using remote sensing and Geographic Information Systems (GIS). Coast wattle was successfully mapped from Landsat ETM imagery using a supervised classification procedure, with 82%, of coast wattle shown on the map accurately depicting coast wattle on the ground. An estimated 11,448 ha were classified as supporting coast wattle, representing 12% of native vegetation in the study area. A more detailed GIS analysis in the Lower Glenelg National Park revealed coast wattle has invaded a limited number of vegetation types, and is more prevalent close to roads and within management zones associated with disturbance. The current regional extent of the species means widespread control is unlikely; hence the immediate focus should be on preventing further spread into areas where it is currently absent. Landsat imagery also proved to be a successful tool for mapping large scale coast wattle distribution, and could be used in long-term monitoring of the species.

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TATA box is one of the most important transcription factor binding sites. But the exact sequences of TATA box are still not very clear yet. In this study, we conducted a dedicated analysis on the frequency distribution of TATA Box and its extension sequences on human promoters. Sixteen TATA elements derived from TATA Box motif, TATAWAWN, were classified into three distribution patterns: peak, bottom-peak and bottom. Fourteen TATA extension sequences (up to two base extensions) were predicted to be the new TATA Box elements because of their high motif factors, which indicate their statistical significance. Statistical analysis on the promoters of mouse, zebrafish and drosophila melanogaster verified seven of these elements. It was also observed that the distribution of TATA elements on the promoters of housekeeping genes are very similar with their distribution on the promoters of tissue specific genes in human.

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Although the development of geographic information system (GIS) technology and digital data manipulation techniques has enabled practitioners in the geographical and geophysical sciences to make more efficient use of resource information, many of the methods used in forming spatial prediction models are still inherently based on traditional techniques of map stacking in which layers of data are combined under the guidance of a theoretical domain model. This paper describes a data-driven approach by which Artificial Neural Networks (ANNs) can be trained to represent a function characterising the probability that an instance of a discrete event, such as the presence of a mineral deposit or the sighting of an endangered animal species, will occur over some grid element of the spatial area under consideration. A case study describes the application of the technique to the task of mineral prospectivity mapping in the Castlemaine region of Victoria using a range of geological, geophysical and geochemical input variables. Comparison of the maps produced using neural networks with maps produced using a density estimation-based technique demonstrates that the maps can reliably be interpreted as representing probabilities. However, while the neural network model and the density estimation-based model yield similar results under an appropriate choice of values for the respective parameters, the neural network approach has several advantages, especially in high dimensional input spaces.

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Accurate assessment of the fate of salts, nutrients, and pollutants in natural, heterogeneous soils requires a proper quantification of both spatial and temporal solute spreading during solute movement. The number of experiments with multisampler devices that measure solute leaching as a function of space and time is increasing. The breakthrough curve (BTC) can characterize the temporal aspect of solute leaching, and recently the spatial solute distribution curve (SSDC) was introduced to describe the spatial solute distribution. We combined and extended both concepts to develop a tool for the comprehensive analysis of the full spatio-temporal behavior of solute leaching. The sampling locations are ranked in order of descending amount of total leaching (defined as the cumulative leaching from an individual compartment at the end of the experiment), thus collapsing both spatial axes of the sampling plane into one. The leaching process can then be described by a curved surface that is a function of the single spatial coordinate and time. This leaching surface is scaled to integrate to unity, and termed S can efficiently represent data from multisampler solute transport experiments or simulation results from multidimensional solute transport models. The mathematical relationships between the scaled leaching surface S, the BTC, and the SSDC are established. Any desired characteristic of the leaching process can be derived from S. The analysis was applied to a chloride leaching experiment on a lysimeter with 300 drainage compartments of 25 cm2 each. The sandy soil monolith in the lysimeter exhibited fingered flow in the water-repellent top layer. The observed S demonstrated the absence of a sharp separation between fingers and dry areas, owing to diverging flow in the wettable soil below the fingers. Times-to-peak, maximum solute fluxes, and total leaching varied more in high-leaching than in low-leaching compartments. This suggests a stochastic–convective transport process in the high-flow streamtubes, while convection–dispersion is predominant in the low-flow areas. S can be viewed as a bivariate probability density function. Its marginal distributions are the BTC of all sampling locations combined, and the SSDC of cumulative solute leaching at the end of the experiment. The observed S cannot be represented by assuming complete independence between its marginal distributions, indicating that S contains information about the leaching process that cannot be derived from the combination of the BTC and the SSDC.

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1. Disturbance and anthropogenic land use changes are usually considered to be key factors facilitating biological invasions. However, specific comparisons of invasion success between sites affected to different degrees by these factors are rare.

2. In this study we related the large-scale distribution of the invading New Zealand mud snail (Potamopyrgus antipodarum) in southern Victorian streams, Australia, to anthropogenic land use, flow variability, water quality and distance from the site to the sea along the stream channel.

3. The presence of P. antipodarum was positively related to an index of flow-driven disturbance, the coefficient of variability of mean daily flows for the year prior to the study.

4. Furthermore, we found that the invader was more likely to occur at sites with multiple land uses in the catchment, in the forms of grazing, forestry and anthropogenic developments (e.g. towns and dams), compared with sites with low-impact activities in the catchment. However, this relationship was confounded by a higher likelihood of finding this snail in lowland sites close to the sea.

5. We conclude that P. antipodarum could potentially be found worldwide at sites with similar ecological characteristics. We hypothesise that its success as an invader may be related to an ability to quickly re-colonise denuded areas and that population abundances may respond to increased food resources. Disturbances could facilitate this invader by creating spaces for colonisation (e.g. a possible consequence of floods) or changing resource levels (e.g. increased nutrient levels in streams with intense human land use in their catchments).

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Background
Little evidence exists to describe expected volumes of chest tube (CT) drainage after coronary artery bypass grafting (CABG).

Objectives
The study objective was to map the trajectory of CT drainage volumes from insertion to removal after CABG.

Design

This was a retrospective, descriptive study.
Patients
The study included 239 patients who underwent CABG at a single metropolitan hospital in Melbourne, Australia.

Results
The sample (N = 234), aged 68.7 years (standard deviation [SD] 9.9), was predominantly male (N = 185, 79.1%). The mean duration of CT insertion was 45.2 hours (SD 26.7), and total drainage volume was 1300.6 mL (SD 763.8). Drainage volumes plateau to 31 mL per hour, 8 hours after surgery. From 24 to 48 hours, the mean drainage was 21 mL per hour. Drainage volumes varied between genders.

Conclusions
Evidence of similar drainage patterns in other populations is difficult to locate. If the pattern of drainage shown in this study is consistent, experimental intervention studies comparing standard removal time and earlier removal are recommended. If not, prospective collection of relevant preoperative, intraoperative, and postoperative factors across multiple sites is necessary to determine which patient or practice variations influence CT drainage patterns after CABG.

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Hyaluronan (HA) is a glycosaminoglycan that is synthesized by a family of enzymes called hyaluronan synthases (HASs), of which there are three isoforms (HAS1, 2 and 3) in mammals. The HASs have different tissue expression patterns and function, indicating that synthesis of HA and formation of the HA matrix may be regulated by various factors. The HA matrix has an important role in renal water handling and the production of a concentrated urine. We investigated the distribution of HA and the expression of HAS1, HAS2 and HAS3 mRNAs in the kidney of the Spinifex hopping mouse, Notomys alexis, a native Australian desert rodent that is reported to produce the most concentrated urine of any mammal. After periods of three, seven and fourteen days of water deprivation, the distribution of renal HA changed considerably, and there was a general down-regulation of HAS mRNA expression. It is proposed that the regulation of HA synthesis by the different HAS isoforms during water deprivation in N. alexis, could be influenced by the molecular mass of the HA chains produced by each isoform, followed by the rate at which the individual HAS produces HA.

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This paper concerns the ways in which public policy regarding the distribution of resources might be used to increase the happiness of the Thai population. The term happiness refers to the subjective side of life quality, which in contemporary science is more commonly referred to as subjective wellbeing (SWB). The SWB construct is described within the theoretical context of SWB homeostasis. This is a proposed management system which has the role of maintaining a positive view of the self It will be described how the homeostatic system can be challenged by hardship. The resources that the system requires to manage such challenges will also be described.  Recommended forms of SWB measurement will be considered. It is concluded that public policy which directs resources to disadvantaged population sectors may be one of the most effective initiatives to enhance population wellbeing and national productivity.