902 resultados para 770409 Estuarine and lagoon areas
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Sporobolus pyramidalis P. Beauv (giant rats tail grass) is a serious agricultural and environmental weed in tropical and subtropical areas of Australia. Infestations of this unpalatable plant reduce the productivity of pastures and the profitability of industries dependent on grazing animals. This paper reports a series of studies undertaken to assist in the development of control strategies for this species. In particular, these studies measured the viability and dormancy status of fresh seed of S. pyramidalis and the decline of dormancy with time. Variability in these characteristics was determined in seeds collected from several sites within south-east Queensland. The effect of moisture availability during the inflorescence and seed production phases on seed viability and dormancy was also determined. The dormancy of freshly collected seed from several sites ranged from 15 to 95%, but decreased to negligible levels after 4-6 months. Seeds that matured under conditions of high moisture availability were initially more dormant than seeds matured where moisture was less readily available. The proportion of viable seeds was significantly lower in smaller than larger seeds even though viability for all seed sizes exceeded 90%. This study has shown that seed of S. pyramidalis generally has high viability with a large proportion of the seed germinable soon after maturity.
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We assessed the impact of large-scale commercial and recreational harvesting of polychaete worms Marphysa spp. on macrobenthic assemblages in a subtropical estuary in Queensland, Australia, by examining: (1) the spatial extent of harvesting activities and the rate of recovery of the seagrass habitat over an 18 to 20 mo period; (2) the recovery of infauna in and around commercial pits of known age; (3) the indirect effects of physical disturbance from trampling and deposition of sediments during harvesting on epibenthos in areas adjacent to commercial and recreational pits; (4) impacts of potential indirect effects through manipulative experimentation. Harvesting caused a loss of seagrass, changes to the topography and compaction of the sediments associated with the creation of walls around commercial pits, and the deposition of rubble dug from within the pit. The walls and rubble were still evident after 1.8 to 20 mo, but comprised only a small proportion of the total area on the intertidal banks. There was a shift from an intertidal area dominated by Zostera capricorni to one with a mixture of Z. capricorni, Halophila spp. and Halodule uninervis, but there was no overall decline in the biomass of seagrass in these areas. There were distinct impacts from harvesting on the abundance of benthic infauna, especially amphipods, polychaetes and gastropods, and these effects were still detectable after 4 mo of potential recovery. After 12 me, there were no detectable differences in the abundances of these infauna between dug areas and reference areas, which suggested that infauna had recovered from impacts of harvesting; however, an extensive bloom of toxic fireweed Lyngbya majsucula may have masked any remaining impacts. There were no detectable impacts of harvesting on epifauna living in the seagrass immediately around commercial or recreational pits.
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Traditional vegetation mapping methods use high cost, labour-intensive aerial photography interpretation. This approach can be subjective and is limited by factors such as the extent of remnant vegetation, and the differing scale and quality of aerial photography over time. An alternative approach is proposed which integrates a data model, a statistical model and an ecological model using sophisticated Geographic Information Systems (GIS) techniques and rule-based systems to support fine-scale vegetation community modelling. This approach is based on a more realistic representation of vegetation patterns with transitional gradients from one vegetation community to another. Arbitrary, though often unrealistic, sharp boundaries can be imposed on the model by the application of statistical methods. This GIS-integrated multivariate approach is applied to the problem of vegetation mapping in the complex vegetation communities of the Innisfail Lowlands in the Wet Tropics bioregion of Northeastern Australia. The paper presents the full cycle of this vegetation modelling approach including sampling sites, variable selection, model selection, model implementation, internal model assessment, model prediction assessments, models integration of discrete vegetation community models to generate a composite pre-clearing vegetation map, independent data set model validation and model prediction's scale assessments. An accurate pre-clearing vegetation map of the Innisfail Lowlands was generated (0.83r(2)) through GIS integration of 28 separate statistical models. This modelling approach has good potential for wider application, including provision of. vital information for conservation planning and management; a scientific basis for rehabilitation of disturbed and cleared areas; a viable method for the production of adequate vegetation maps for conservation and forestry planning of poorly-studied areas. (c) 2006 Elsevier B.V. All rights reserved.
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Alcoholism results in changes in the human brain which reinforce the cycle of craving and dependency, and these changes are manifest in the pattern of expression of mRNA and proteins in key cells and brain areas. Long-term alcohol abuse also results in damage to selected regions of the cortex. We have used cDNA microarrays to show that less than 1% of mRNA transcripts differ signifi cantly between cases and controls in the susceptible area and that the expression profi le of a subset of these transcripts is suffi cient to distinguish alcohol abusers from controls. In addition, we have utilized a 2D gel proteomics based approach to determine the identity of proteins in the superior frontal cortex (SFC) of the human brain that show differential expression in controls and long term alcohol abusers. Overall, 182 proteins differed by the criterion of > 2-fold between case and control samples. Of these, 139 showed signifi cantly lower expression in alcoholics, 35 showed signifi cantly higher expression, and 8 were new or had disappeared. To date 63 proteins have been identifi ed. The expression of one family of proteins, the synucleins, has been further characterized using Real Time PCR and Western Blotting. The expression of alpha-synuclein mRNA was signifi cantly lower in the SFC of alcoholics compared with the same area in controls (P = 0.01) whereas no such difference in expression was found in the motor cortex. The expression of beta- and gamma- synuclein were not signifi cantly different between alcoholics and controls. In contrast, the pattern of alphasynuclein protein expression differs from that of the corresponding RNA transcript. Because of the key role of synaptic proteins in the pathogenesis of alcoholism, we are developing 2-D DIGE based techniques to quantify expression changes in synaptosomes prepared from the SFC of controls and alcoholics.
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As a means of benchmarking their position and assisting with anticipating an uncertain future, the identification of critical information systems (IS) management issues frameworks is becoming an increasingly important research task for both academics and industrialists. This paper provides a description and summary of previous work on identifying IS issues frameworks by reviewing 20 research investigations in terms of what they studied and how they were conducted. It also suggests some possible directions and methodologies for future research. The summary and suggestions for further work are applicable for issues framework research in the IS management field as well as in other business and management areas.
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Many students starting courses in business, accounting and similar areas want to update their mathematical skills, and are seeking a suitable text; this book addresses their needs. Written in an informal style, emphasising understanding and application of techniques rather than formal proofs, it covers all the mathematics needed by entrants to BTEC, undergraduate, MBA and related professional courses. Plentiful worked examples and exercises with solutions make the book a practical self-study aid for those wishing to revise before starting their course.
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Objective: To study the topography of neurofibrillary tangles (NFT) in cortical and subcortical areas in progressive supranuclear palsy (PSP). Methods: Pattern analysis was carried out on tau-positive NFT in eight PSP cases. Results: Of the areas studied, NFT were randomly distributed in 68%, regularly distributed in 3%, and clustered in 29%. A regular distribution of clusters was more frequent in cortical than subcortical areas. Conclusion: NFT topography in subcortical areas was similar to inclusions in the synucleinopathy multiple system atrophy (MSA) but in cortical areas was comparable to other tauopathies. © 2006 Elsevier Ltd. All rights reserved.
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Following an introductory chapter, I examine (i) typologies which have differentiated the literature on organisational culture and symbolism (Chapter 2), (ii) the contribution of organisation theory to organisation culture (Chapter 3), and (iii) recent literature on organisational culture and symbolism (Chapter 4). Within these chapters, I adopt Habermas' (1972) notion of knowledge-constitutive interests, assessing the contrubutions to understanding organisational culture made by literature guided by technical, practical and emancipatory cognitive interests. In doing so, I suggest that more critical studies on organisational culture and symbolism have been comparatively neglected. Lamenting this neglect, I suggest that Giddens' theory of structuration can be employed to advance the development of a critical, emancipatory conceptualisation of organisational culture. In particular, I argue that this Giddensian analysis, by penetrating the existential, poltical and material processes of cultural reproduction (Chapter 5), is able to disclose some of the more contradictory features of organisation culture. The remainder of the thesis comprises of a critical ethnography of the work cultures of public relations and personnel specialists located in a state bureaucracy. I begin the ethnography with a dicussion of my research methods (Chapter 6) and an overview of the departments studied (Chapter 7): I then examine (i) the work cultures of the specialists (Chapter 8), (ii) the specialists' management of the relationships with the hosts bureaucracy (Chapter 9); and, (iii) opportunities the specialists had for developing an emancipatory praxis (Chapter 10). Finally, in a concluding section, I offer some critical reflections on the contributions of the thesis and suggest areas for future research.
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This thesis covers two major aspects of pharmacy education; undergraduate education and pre-registration training. A cohort of pharmacy graduates were surveyed over a period of four years, on issues related to undergraduate education, pre-registration training and continuing education. These graduates were the first-ever to sit the pre-registration examination. In addition, the opinions of pre-registration tutors were obtained on pre-registration training, during the year that competence-based assessment was introduced. It was concluded that although the undergraduate course provided a broad base of knowledge suitable for graduates in all branches of pharmacy, several issues were identified which would require attention in future developments of the course. These were: 1. the strong support for the expansion of clinical, social and practice-based teaching. 2. the strong support to retain the scientific content to the same extent as in the three-year course. 3. a greater use of problem-based learning methods. The graduates supported the provision of a pre-registration continuing education course to help prepare for the examination and in areas inadequately covered in the undergraduate course. There was also support for the introduction of some form of split branch training. There was no strong evidence to suggest that the training had been an application of undergraduate education. In general, competence-based training was well regarded by tutors as an appropriate and effective method of skill assessment. However, community tutors felt it was difficult to carry out effectively due to day-to-day time constraints. The assistant tutors in hospital pharmacy were found to have a very important role in provision of training, and should be adequately trained and supported. The study recommends the introduction of uniform training and a quality assurance mechanism for all tutors and assistants undertaking this role.
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The work described in the following pages was carried out at various sites in the Rod Division of the Delta Metal Company. Extensive variation in the level of activity in the industry during the years 1974 to I975 had led to certain inadequacies being observed 1n the traditional cost control procedure. In an attempt to remedy this situation it was suggested that a method be found of constructing a system to improve the flexibility of cost control procedures. The work involved an assimilation of the industrial and financial environment via pilot studies which would later prove invaluable to home in on the really interesting and important areas. Weaknesses in the current systems which came to light made the methodology of data collection and the improvement of cost control and profit planning procedures easier to adopt. Because of the requirements of the project to investigate the implications of Cost behaviour for profit planning and control, the next stage of the research work was to utilise the on-site experience to examine at a detailed level the nature of cost behaviour. The analysis of factory costs then showed that certain costs, which were the most significant exhibited a stable relationship with respect to some known variable, usually a specific measure of Output. These costs were then formulated in a cost model, to establish accurate standards in a complex industrial setting in order to provide a meaningful comparison against which to judge actual performance. The necessity of a cost model was •reinforced by the fact that the cost behaviour found to exist was, in the main, a step function, and this complex cost behaviour, the traditional cost and profit planning procedures could not possibly incorporate. Already implemented from this work is the establishment of the post of information officer to co-ordinate data collection and information provision.
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Attention defines our mental ability to select and respond to stimuli, internal or external, on the basis of behavioural goals in the presence of competing, behaviourally irrelevant, stimuli. The frontal and parietal cortices are generally agreed to be involved with attentional processing, in what is termed the 'fronto-parietal' network. The left parietal cortex has been seen as the site for temporal attentional processing, whereas the right parietal cortex has been seen as the site for spatial attentional processing. There is much debate about when the modulation of the primary visual cortex occurs, whether it is modulated in the feedforward sweep of processing or modulated by feedback projections from extrastriate and higher cortical areas. MEG and psychophysical measurements were used to look at spatially selective covert attention. Dual-task and cue-based paradigms were used. It was found that the posterior parietal cortex (PPC), in particular the SPL and IPL, was the main site of activation during these experiments, and that the left parietal lobe was activated more strongly than the right parietal lobe throughout. The levels of activation in both parietal and occipital areas were modulated in accordance with attentional demands. It is likely that spatially selective covert attention is dominated by the left parietal lobe, and that this takes the form of the proposed sensory-perceptual lateralization within the parietal lobes. Another form of lateralization is proposed, termed the motor-processing lateralization, the side of dominance being determined by handedness, being reversed in left- relative to right-handers. In terms of the modulation of the primary visual cortex, it was found that it is unlikely that V1 is modulated initially; rather the modulation takes the form of feedback from higher extrastriate and parietal areas. This fits with the idea of preattentive visual processing, a commonly accepted idea which, in itself, prevents the concept of initial modulation of V1.
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The recognition of faces and of facial expressions in an important evolutionary skill, and an integral part of social communication. It has been argued that the processing of faces is distinct from the processing of non-face stimuli and functional neuroimaging investigations have even found evidence of a distinction between the perception of faces and of emotional expressions. Structural and temporal correlates of face perception and facial affect have only been separately identified. Investigation neural dynamics of face perception per se as well as facial affect would allow the mapping of these in space, time and frequency specific domains. Participants were asked to perform face categorisation and emotional discrimination tasks and Magnetoencephalography (MEG) was used to measure the neurophysiology of face and facial emotion processing. SAM analysis techniques enable the investigation of spectral changes within specific time-windows and frequency bands, thus allowing the identification of stimulus specific regions of cortical power changes. Furthermore, MEG’s excellent temporal resolution allows for the detection of subtle changes associated with the processing of face and non-face stimuli and different emotional expressions. The data presented reveal that face perception is associated with spectral power changes within a distributed cortical network comprising occipito-temporal as well as parietal and frontal areas. For the perception of facial affect, spectral power changes were also observed within frontal and limbic areas including the parahippocampal gyrus and the amygdala. Analyses of temporal correlates also reveal a distinction between the processing of faces and facial affect. Face perception per se occurred at earlier latencies whereas the discrimination of facial expression occurred within a longer time-window. In addition, the processing of faces and facial affect was differentially associated with changes in cortical oscillatory power for alpha, beta and gamma frequencies. The perception of faces and facial affect is associated with distinct changes in cortical oscillatory activity that can be mapped to specific neural structures, specific time-windows and latencies as well as specific frequency bands. Therefore, the work presented in this thesis provides further insight into the sequential processing of faces and facial affect.
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The role of the European Union in global politics has been of growing interest over the past decade. The EU is a key player in global institutions such as the World Trade Organization (WTO) and NATO. It continues to construct an emerging identity and project its values and interests throughout contemporary international relations. The capacity of the EU to both formulate and realise its goals, however, remains contested. Some scholars claim the EU’s `soft power’ attitude rivals that of the USA’s `hard power’ approach to international relations. Others view the EU as insufficiently able to produce a co-ordinated position to project upon global politics. Regardless of the position taken within this debate, the EU’s relationship with its external partners has an increasingly important impact upon economic, political and security concerns on an international level. Trade negotiations, military interventions, democracy promotion, international development and responses to the global economic crisis have all witnessed the EU playing a central role. This has seen the EU become both a major force in contemporary institutions of global governance and a template for supranational governance that might influence other attempts to construct regional and global institutions. This volume brings together a collection of leading EU scholars to provide a state-of-the-art overview covering these and other debates relating to the EU’s role in contemporary global governance. The Handbook is divided into four main sections: Part I: European studies and global governance – provides an overview and critical assessment of the leading theoretical approaches through which the EU’s role in global governance has been addressed within the literature. Part II: Institutions – examines the role played by the key EU institutions in pursuing a role for the EU in contemporary international relations. Part III: Policy and issue areas – explores developments within particular policy sectors, assessing the different impact that the EU has had in different issue areas, including foreign and security policy, environmental policy, common commercial policy, the Common Agricultural Policy, development policy, accession policy, the Neighbourhood Policy and conflict transformation. Part IV: The global multilevel governance complex and the EU – focuses on the relationship between the EU and the institutions, regions and countries with which it forms a global multilevel governance complex, including chapters on the EU’s relationship with the WTO, United Nations, East Asia, Africa and the USA.
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The technique of remote sensing provides a unique view of the earth's surface and considerable areas can be surveyed in a short amount of time. The aim of this project was to evaluate whether remote sensing, particularly using the Airborne Thematic Mapper (ATM) with its wide spectral range, was capable of monitoring landfill sites within an urban environment with the aid of image processing and Geographical Information Systems (GIS) methods. The regions under study were in the West Midlands conurbation and consisted of a large area in what is locally known as the Black Country containing heavy industry intermingled with residential areas, and a large single active landfill in north Birmingham. When waste is collected in large volumes it decays and gives off pollutants. These pollutants, landfill gas and leachate (a liquid effluent), are known to be injurious to vegetation and can cause stress and death. Vegetation under stress can exhibit a physiological change, detectable by the remote sensing systems used. The chemical and biological reactions that create the pollutants are exothermic and the gas and leachate, if they leave the waste, can be warmer than their surroundings. Thermal imagery from the ATM (daylight and dawn) and thermal video were obtained and used to find thermal anomalies on the area under study. The results showed that vegetation stress is not a reliable indicator of landfill gas migration, as sites within an urban environment have a cover too complex for the effects to be identified. Gas emissions from two sites were successfully detected by all the thermal imagery with the thermal ATM being the best. Although the results were somewhat disappointing, recent technical advancements in the remote sensing systems used in this project would allow geo-registration of ATM imagery taken on different occasions and the elimination of the effects of solar insolation.
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Several axi-symmetric EN3B steel components differing in shape and size were forged on a 100 ton joint knuckle press. A load cell fitted under the lower die inserts recorded the total deformation forces. Job parameters were measured off the billets and the forged parts. Slug temperatures were varied and two lubricants - aqueous colloidal graphite and oil - were used. An industrial study was also conducted to check the results of the laboratory experiments. Loads were measured (with calibrated extensometers attached to the press frames) when adequately heated mild steel slugs were being forged in finishing dies. Geometric parameters relating to the jobs and the dies were obtained from works drawings. All the variables considered in the laboratory study could not, however, be investigated without disrupting production. In spite of this obvious limitation, the study confirmed that parting area is the most significant geometric factor influencing the forging load. Multiple regression analyses of the laboratory and industrial results showed that die loads increase significantly with the weights and parting areas of press forged components, and with the width to thickness ratios of the flashes formed, but diminish with increasing slug temperatures and higher billet diameter to height ratios. The analyses also showed that more complicated parts require greater loads to forge them. Die stresses, due to applied axial loads, were investigated by the photoelastic method. The three dimensional frozen stress technique was employed. Model dies were machined from cast araldite cylinders, and the slug material was simulated with plasticene. Test samples were cut from the centres of the dies after the stress freezing. Examination of the samples, and subsequent calculations, showed that the highest stresses were developed in die outer corners. This observation partly explains why corner cracking occurs frequently in industrial forging dies. Investigation of die contact during the forging operation revealed the development of very high stresses.