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Although, wind turbines have traditionally been sited in open terrain, there is a growing trend of installing turbines in non-homogeneous terrain, such as urban areas. Recorded urban turbine failures suggest that turbine design has been inadequate for the turbulence experienced at these sites and hence a better understanding of the turbine-loading issues in the built environment is required. This paper compares turbine blade load statistics for inflow turbulence fields based on the open terrain standard Kaimal spectra, as suggested in the standard IEC61400-2 that covers the design and safety standard of small wind turbines, and measured turbulence spectra from a built environment site. The findings show that for extreme, high turbulent intensity winds, the measured spectra predict isolated loading events around twice the magnitude of loads predicted by use of the standard spectra. The work suggests the need for improvements to the standard in order to model the non-Gaussian wind statistics that occur in extreme events such as sudden strong gusts.

Background Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus. Methods and Results A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments. Conclusions Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Small wind turbines are often sited in more complex environments than the open terrain sites assumed in relevant installation guidelines or in the international small wind turbine design standard IEC61400-2. The built environment is an example of such a complex environment and installation of small wind turbines on the rooftops of high buildings has been suggested by architects and project developers as a potential means of incorporating sustainable energy generation into building design. In the absence of guidelines for installing wind turbines in the built environment, two key wind measurement parameters are the rate at which a data acquisition system (DAQ) samples the sensor, and the period over which the sampled data is averaged. This paper presents the results of the effect of sampling rate and averaging period on turbulence measurements from a monitoring system on a building rooftop, in order to inform the process of developing guidelines. The results will inform the development of a Recommended Practice of wind resource assessment in the built environment, via the International Energy Agency Task 27. The key finding of the paper is that, in general, 10 Hz sampling and 10 min averaging period give upper estimates for turbulence intensity and maximum values of the turbulence power spectra. Using these conservative values in the design of the turbine may be the best approach to ensure that the turbine can handle both the fatigue loads and resonance due to gusts.

The use of small grid-connected wind turbines is increasing within the built environment, yet atmospheric turbulence in this environment is more complex than the open terrain sites on which the turbine design standards are based. The current IEC61400-2 design standard uses stochastic turbulence models adapted from the von Karman and Kaimal power spectra in order to simulate flow fields that are used by designers to predict structural loading on small wind turbines. Both spectra are based on observations in the atmospheric surface layer developed over flat, smooth and uniform terrain yet IEC61400-2 does not offer any modifications of the spectra for more complex terrain such as that which exists in the built environment. This paper investigates the extent to which the von Karman and Kaimal models, as presented in IEC61400-2, are appropriate for use in the design of SWTs installed on the rooftop of a warehouse in the built environment. In particular the paper attempts to gauge how different the turbulence spectra currently used for turbine design are from the actual inflow conditions experienced by the turbines on the roof. The power spectra of all three wind components in neutral and slightly unstable atmospheric conditions at four heights above the rooftop are considered. A degree of misfit function was used to compare von Karman, Kaimal and measured power spectra, as an indicator of model suitability. A sensitivity study was carried out to assess the influence of turbulence length scale and wind direction on the results. The Kaimal spectral function was the better of the existing models in predicting the trends of all wind components and was used as a starting point in developing an approach to modelling turbulence power spectra for a rooftop site in the built environment by incorporating typical length scales at the site.

The installation of small and medium-size wind turbines on the rooftops of high buildings has been often suggested by architects and project developers as a potential solution for achieving sustainable energy in building design. In such locations, however, because of the presence of buildings and other adjacent obstructions, wind is normally turbulent, unstable and weak, in terms of direction and speed. The use of wind turbines in the built environment poses challenges to overcome, including energy yield reduction due to lower mean wind speeds in urban areas, and environmental impacts because of their close vicinity to people and property. There is a need to understand the inflow wind conditions for a small wind turbine in the built-environment. A resource assessment of the potential wind turbine site in the built environment can determine the wind characteristics including zones of wind acceleration, recirculation, blocking and channelling. This knowledge is crucial for input into the design process of a small wind turbine to accurately predict blade fatigue loads and ensure that it operates safely, and performs optimally in the environment. Computational Fluid Dynamics (CFD) is a useful method to model wind flows in order to perform a resource assessment for the application of small wind turbines in a manner that requires less time and investment than a measurement campaign. This paper presents the results of research using a CFD code to model wind flows over the roof of a building and assesses the possibility of combining a CFD package with wind atlas software to form a wind energy resource assessment tool for the application of small wind turbines on the roof of a building. Experimentation with the model shows that the results are particularly sensitive to building height and shape, roof shape, wind direction, and turbine installation height and location. The results will be used to help develop a recommended practice of wind resource assessment in the built environment, in an international collaborative effort via the International Energy Agency Task 27.

The complex problems associated with global change processes calls for close collaboration between science disciplines to create new, integrated knowledge. In the wake of global change processes, forests and other natural environments have been rapidly changing, highlighting the need for collaboration and integrative research development. Few tools are available to explore the potential for collaborations in research ventures that are just starting up. This study presents a useful approach for exploring and fostering collaborations between academics working in research teams and organizations comprising multiple science disciplines (i.e., multi-disciplinary). The research aim was to reveal potential barriers, common ground, and research strengths between academics working in a new centre focused on forest and climate change research. This aim was based on the premise that raising awareness and working with this acquired knowledge fosters collaborations and integrative research development. An email survey was deployed amongst the academics to obtain: (i) their understanding of common themes (e.g., climate change, scale of investigation, woodland/forest health/decline), (ii) descriptions of the spatial and temporal scales of their research, and (iii) their approach and perceived contributions to climate change research. These data were analysed using a semi-quantitative content analysis approach. We found that the main potential barriers were likely to be related to differences in understanding of the common research themes, whilst similarities and disciplinary strengths provided critical elements to foster collaborations. These findings were presented and discussed amongst the centre academics to raise awareness and create a dialogue around these issues. This process resulted in the development of four additional research projects involving multiple disciplines. The approach used in this study provides a useful methodology of broader benefit to similar multi-disciplinary research teams and organizations elsewhere.

The importance of ecological management for reducing the vulnerability of biodiversity to climate change is increasingly recognized, yet frameworks to facilitate a structured approach to climate adaptation management are lacking. We developed a conceptual framework that can guide identification of climate change impacts and adaptive management options in a given region or biome. The framework focuses on potential points of early climate change impact, and organizes these along two main axes. First, it recognizes that climate change can act at a range of ecological scales. Secondly, it emphasizes that outcomes are dependent on two potentially interacting and countervailing forces: (1) changes to environmental parameters and ecological processes brought about by climate change, and (2) responses of component systems as determined by attributes of resistance and resilience. Through this structure, the framework draws together a broad range of ecological concepts, with a novel emphasis on attributes of resistance and resilience that can temper the response of species, ecosystems and landscapes to climate change. We applied the framework to the world’s largest remaining Mediterranean-climate woodland, the ‘Great Western Woodlands’ of south-western Australia. In this relatively intact region, maintaining inherent resistance and resilience by preventing anthropogenic degradation is of highest priority and lowest risk. Limited, higher risk options such as fire management, protection of refugia and translocation of adaptive genes may be justifiable under more extreme change, hence our capacity to predict the extent of change strongly impinges on such management decisions. These conclusions may contrast with similar analyses in degraded landscapes, where natural integrity is already compromised, and existing investment in restoration may facilitate experimentation with higher risk options.

A simple model is developed to analyse the surface energy balance from satellite observations for south-western Australia. This illustrates that the replacement of native vegitation with agriculture based on a winter growing annual species has led to a marked reduction in the sensible heat flux to the atmosphere during winter and spring. It is suggested that this reduction may be related to the observed decrease in winter rainfall observed throughout the agricultural region.

Following the clearing of native perennial vegetation for agriculture based on winter growing annual species, the surface characteristics of south-western Australia have been significantly altered. Analysis of the annual variation of these characteristics based on satellite data and a one-dimensional boundary layer model suggests that convective mixing over the cleared land is no longer able to reach the lifting condensation level for a significant period of the year. This implies a decrease in convective cloud formation and a reduction in the convective enhancement of rainfall.

Southwestern Australia, with a semiarid Mediterranean climate, has been extensively cleared of native vegetation for winter-growing agricultural species. The resultant reduction in evapotranspiration has increased land salinisation. Through detailed meteorological and vegetation measurements over both agricultural and native vegetation, the bunny fence experiment is addressing the impact on the climate of replacing native perennial vegetation with winter-growing annual species. Such measurements will give a better understanding of the interaction between the land surface and the atmosphere and are important for improved parameterization of the boundary layer in climate models.

Homogeneous urban areas defined through an urban ecology approach are used to sample traffic patterns for a series of cross city driving cycles in Perth, Western Australia. These driving cycles, including a whole city cycle, are presented for peak and off-peak driving. The cycles are validated by relating them back to the urban ecology of Perth through a simple model based on traffic events (intersection and vehicle-related events). The implications for developing a more fundamental theory of urban driving are examined, and in particular the link between increased road capacity and lowered fuel use and emissions is seriously questioned.

A comparison between a numerical mesoscale model and the computationally simpler flow model developed as part of the European wind atlas is presented. Despite observed horizontal variations in topographically induced mesoscale forcing which is not incorporated in the simpler model, there is general agreement on an order of magnitude assessment of the wind energy variations. The range of applicability of such simpler wind energy assessment models is shown to be limited to regions where the mesoscale forcing inherent in the base observations has not varied appreciably.

Representative driving cycles across the Perth, Western Australia, metropolitan region illustrate a direct relationship to urban land use. Movement away from the central business district results in fewer traffic events, higher speeds, longer cruise periods and shorter stops. The consequent reduction in root mean square acceleration leads to a corresponding reduction in vehicle emission factors. Urban planning implications are pursued and highlight the importance of public transport as an option in reducing urban air pollution.

Previous studies have suggested that mesoscale processes are important in determining available wind energy potential in southern Australia. These effects are quantified by application of a numerical mesoscale model to the Swan coastal plain of Western Australia, illustrating that the wind power potential in this area is dominated by the sea breeze circulation and topographical influences. While sea breezes are a common feature of the summer climate, they are a significant source of wind energy only under weak synoptic flows, whereas mesoscale topographical effects are significant under all synoptic conditions.

A range of separate traffic and corridor studies from Perth are analyzed together with an international comparison of thirty-two cities to seek an answer to this question. The data suggest that free flowing traffic does not save energy or lower emissions overall in a city despite the apparently clear advantages for individual vehicles. The mechanisms for this in terms of travel distances, alternative modes and sub optimal vehicle usage are outlined together with the characteristics of cities where lower fuel use is apparent. Some implications for urban road project justification and traffic engineering practice are suggested.

Solar irradiance is estimated on the basis of three hourly cloud observations and compared with the measured irradiance. This indicates that it is possible to predict daily global irradiation to within 15% and thus illustrates the potential for extending the solar energy data base available for heliotechnology in Western Australia.

A technique is developed for synthesising a statistically representative driving cycle for an urban area based on dynamic driving data collected by the chase car technique. The simulation procedure based on a “Knight's Tour” concept relies on an understanding of the dynamics of urban driving, in particular the observed tendency to maintain constant acceleration and deceleration rates. The final synthesised cycle is a representative real driving trace although the analysis raises questions about the level of resolution currently required for driving cycle work.

Forty-two cases of open fractures of the tibia treated by external fixation are presented. Forty-three per cent of patients developed sepsis around one or more pins. Pin track sepsis occurred in 78 per cent of cases involving transfixion pins through muscle and bone but in only 17 per cent of cases using transcutaneous half-pins. Malalignment of more than 5 degrees in any plane was seen in 38 per cent of cases, almost half of which increased in plaster after removal of the fixator.

Four cases of cervical thymic cyst are described. Clinical and microscopic appearances are reviewed, with reference to its distinction from branchial cyst. The use of monoclonal antibodies to cytokeratin as a histologic aid to diagnosis is discussed.

A comparison between observed and modelled wind profiles at an operational wind turbine site highlights the inability of a neutral flow model to accurately predict the flow under low to moderate wind speeds. The importance of these flow conditions to power generation is demonstrated.

A dose of 50 mg of acarbose was administered with a standard breakfast to 13 subjects with dumping syndrome. Significant attenuation of hyperglycaemia (p less than 0.01) was observed, and rises in plasma gastric inhibitory polypeptide, insulin and enteroglycagon were reduced (p less than 0.05). Plasma levels of neurotensin, vasoactive intestinal polypeptide and somatostatin were not affected. Dumping score was reduced, but this did not achieve statistical significance. In a longer-term study, 9 patients took acarbose, 50 mg t.i.d., for 1 month. No significant reduction in the number or severity of dumping attacks was observed, but a majority expressed a preference for the drug and some individuals experienced a marked improvement of symptoms.

The Southwest Australian region has large homogeneous tracts of differing vegetation types separated by a sharp transition called the vermin or bunny fence which runs for almost 750 km. Seasonal winter agriculture is found to the west of the fence, whereas to the east native perennial vegetation grows. Geostationary Meteorological Satellite-5 imagery are used to construct monthly cumulus cloud frequency of occurrence maps for the region 0800 to 1500 LT in hourly increments for 1999 and 2000. Moderate Resolution Imaging Spectroradiometer (MODIS) imagery are used to retrieve regional values of surface temperature, albedo, Normalized Difference Vegetation Index, fractional soil moisture availability, sensible and latent heat fluxes. High spatial resolution Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery are used to retrieve detailed values along the fence. MODIS imagery also is utilized to retrieve cloud optical thickness, droplet sizes, and liquid water paths. This study shows that higher soil moisture availability is found over agricultural areas during winter (September) and over native vegetation areas during summer (December). Latent heat fluxes are higher over native vegetation than over agricultural areas during summer, while sensible heat fluxes are lower. Cumulus clouds occur with higher frequency and have higher optical thicknesses, cloud liquid water contents, and effective radii over agricultural areas during the winter and over native perennial vegetation during the dry summer. This is due to higher latent heat fluxes and available energy over agriculture during winter and over native vegetation during summer. We conclude that land use differences result in differences in available soil moisture and surface energy fluxes, which in turn lead to the observed preferential enhancement of cumulus cloudiness and cumulus cloud properties.