353 resultados para TEMPERATURE-SENSITIVE MUTANT


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Concepts used in this chapter include: Thermoregulation:- Thermoregulation refers to the body’s sophisticated, multi-system regulation of core body temperature. This hierarchical system extends from highly thermo-sensitive neurons in the preoptic region of the brain proximate to the rostral hypothalamus, down to the brain stem and spinal cord. Coupled with receptors in the skin and spine, both central and peripheral information on body temperature is integrated to inform and activate the homeostatic mechanisms which maintain our core temperature at 37oC.1 Body heat is lost through the skin, via respiration and excretions. The skin is perhaps the most important organ in regulating heat loss. Hyporthermia:- Hypothermia is defined as core body temperature less than 350C and is the result of imbalance between the body’s heat production and heat loss mechanisms. Hypothermia may be accidental, or induced for clinical benefit i.e: neurological protection (therapeutic hypothermia). External environmental conditions are the most common cause of accidental hypothermia, but not the only causes of hypothermia in humans. Other causes include metabolic imbalance; trauma; neurological and infectious disease; and exposure to toxins such as organophosphates. Therapeutic Hypothermia:- In some circumstances, hypothermia can be induced to protect neurological functioning as a result of the associated decrease in cerebral metabolism and energy consumption. Reduction in the extent of degenerative processes associated with periods of ischaemia such as excitotoxic cascade; apoptotic and necrotic cell death; microglial activation; oxidative stress and inflammation associated with ischaemia are averted or minimised.2 Mild hypothermia is the only effective treatment confirmed clinically for improving the neurological outcomes of patient’s comatose following cardiac arrest.3

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The aim of the present study was to determine the effect of carbohydrate (CHO; sucrose) ingestion and environmental heat on the development of fatigue and the distribution of power output during a 16.1-km cycling time trial. Ten male cyclists (Vo(2max) = 61.7 +/- 5.0 ml.kg(-1).min(-1), mean +/- SD) performed four 90-min constant-pace cycling trials at 80% of second ventilatory threshold (220 +/- 12 W). Trials were conducted in temperate (18.1 +/- 0.4 degrees C) or hot (32.2 +/- 0.7 degrees C) conditions during which subjects ingested either CHO (0.96 g.kg(-1).h(-1)) or placebo (PLA) gels. All trials were followed by a 16.1-km time trial. Before and immediately after exercise, percent muscle activation was determined using superimposed electrical stimulation. Power output, integrated electromyography (iEMG) of vastus lateralis, rectal temperature, and skin temperature were recorded throughout the trial. Percent muscle activation significantly declined during the CHO and PLA trials in hot (6.0 and 6.9%, respectively) but not temperate conditions (1.9 and 2.2%, respectively). The decline in power output during the first 6 km was significantly greater during exercise in the heat. iEMG correlated significantly with power output during the CHO trials in hot and temperate conditions (r = 0.93 and 0.73; P < 0.05) but not during either PLA trial. In conclusion, cyclists tended to self-select an aggressive pacing strategy (initial high intensity) in the heat.

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The thermal decomposition and dehydroxylation process of coal-bearing strata kaolinite–potassium acetate intercalation complex (CSKK) has been studied using X-ray diffraction (XRD), infrared spectroscopy (IR), thermal analysis, mass spectrometric analysis and infrared emission spectroscopy. The XRD results showed that the potassium acetate (KAc) have been successfully intercalated into coal-bearing strata kaolinite with an obvious basal distance increase of the first basal peak, and the positive correlation was found between the concentration of intercalation regent KAc and the degree of intercalation. As the temperature of the system is raised, the formation of KHCO3, KCO3 and KAlSiO4, which is derived from the thermal decomposition or phase transition of CSKK, is observed in sequence. The IR results showed that new bands appeared, the position and intensities shift can also be found when the concentration of intercalation agent is raised. The thermal analysis and mass spectrometric analysis results revealed that CSKK is stable below 300 °C, and the thermal decomposition products (H2O and CO2) were further proved by the mass spectrometric analysis. A comparison of thermal analysis results of original coal-bearing strata kaolinite and its intercalation complex gives new discovery that not only a new mass loss peak is observed at 285 °C, but also the temperature of dehydroxylation and dehydration of coal bearing strata kaolinite is decreased about 100 °C. This is explained on the basis of the interlayer space of the kaolinite increased obviously after being intercalated by KAc, which led to the interlayer hydrogen bonds weakened, enables the dehydroxylation from kaolinite surface more easily. Furthermore, the possible structural model for CSKK has been proposed, with further analysis required in order to prove the most possible structures.

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Series reactors are used in distribution grids to reduce the short-circuit fault level. Some of the disadvantages of the application of these devices are the voltage drop produced across the reactor and the steep front rise of the transient recovery voltage (TRV), which generally exceeds the rating of the associated circuit breaker. Simulations were performed to compare the characteristics of a saturated core High-Temperature Superconducting Fault Current Limiter (HTS FCL) and a series reactor. The design of the HTS FCL was optimized using the evolutionary algorithm. The resulting Pareto frontier curve of optimum solution is presented in this paper. The results show that the steady-state impedance of an HTS FCL is significantly lower than that of a series reactor for the same level of fault current limiting. Tests performed on a prototype 11 kV HTS FCL confirm the theoretical results. The respective transient recovery voltages (TRV) of the HTS FCL and an air core reactor of comparable fault current limiting capability are also determined. The results show that the saturated core HTS FCL has a significantly lower effect on the rate of rise of the circuit breaker TRV as compared to the air core reactor. The simulations results are validated with shortcircuit test results.

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A method of making full use of the durable strain which fiber Bragg grating (FBG) can undertake is presented, which hugely improves the sensitivities of FBG temperature sensors at high temperature. When a sensor is manufactured at room temperature, its FBG should be given a pre-relaxing length according to the temperature it is asked to measure; once the temperature rise to the asked one, its FBG starts to be stretched and it starts to work with high sensitivity. The relationship between the pre-relaxing length and the working temperature is analyzed. In experiments, when the pre-relaxing lengths are 0.2mm、0.5mm、0.6mm, the working temperatures rise 25℃、50℃、61℃, respectively, and the sensitivities are almost the same (675pm/℃). The facts that the experimental results agree well with the theoretical analyses verify this method’s validity.

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Parabolic Trough Concentrators (PTC) are the most proven solar collectors for solar thermal power plants, and are suitable for concentrating photovoltaic (CPV) applications. PV cells are sensitive to spatial uniformity of incident light and the cell operating temperature. This requires the design of CPV-PTCs to be optimised both optically and thermally. Optical modelling can be performed using Monte Carlo Ray Tracing (MCRT), with conjugate heat transfer (CHT) modelling using the computational fluid dynamics (CFD) to analyse the overall designs. This paper develops and evaluates a CHT simulation for a concentrating solar thermal PTC collector. It uses the ray tracing work by Cheng et al. (2010) and thermal performance data for LS-2 parabolic trough used in the SEGS III-VII plants from Dudley et al. (1994). This is a preliminary step to developing models to compare heat transfer performances of faceted absorbers for concentrating photovoltaic (CPV) applications. Reasonable agreement between the simulation results and the experimental data confirms the reliability of the numerical model. The model explores different physical issues as well as computational issues for this particular kind of system modeling. The physical issues include the resultant non-uniformity of the boundary heat flux profile and the temperature profile around the tube, and uneven heating of the HTF. The numerical issues include, most importantly, the design of the computational domain/s, and the solution techniques of the turbulence quantities and the near-wall physics. This simulation confirmed that optical simulation and the computational CHT simulation of the collector can be accomplished independently.

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Semiconducting metal oxide based gas sensors usually operate in the temperature range 200–500 °C. In this paper, we present a new WO3 thin film based gas sensor for H2 and C2H5OH, operating at 150 °C. Nanostructured WO3 thin films were synthesized by thermal evaporation method. The properties of the as-deposited films were modified by annealing in air at 300 °C and 400 °C. Various analytical techniques such as AFM, TEM, XPS, XRD and Raman spectroscopy have been employed to characterize their properties. A clear indication from TEM and XRD analysis is that the as-deposited WO3 films are highly amorphous and no improvement is observed in the crystallinity of the films after annealing at 300 °C. Annealing at 400 °C significantly improved the crystalline properties of the films with the formation of about 5 nm grains. The films annealed at 300 °C show no response to C2H5OH (ethanol) and a little response to H2, with maximum response obtained at 280 °C. The films annealed at 400 °C show a very good response to H2 and a moderate response to C2H5OH (ethanol) at 150 °C. XPS analysis revealed that annealing of the WO3 thin films at 400 °C produces a significant change in stoichiometry, increasing the number of oxygen vacancies in the film, which is highly beneficial for gas sensing. Our results demonstrate that gas sensors with significant performance at low operating temperatures can be obtained by annealing the WO3 films at 400 °C and optimizing the crystallinity and nanostructure of the as-deposited films.

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Highly sensitive infrared (IR) cameras provide high-resolution diagnostic images of the temperature and vascular changes of breasts. These images can be processed to emphasize hot spots that exhibit early and subtle changes owing to pathology. The resulting images show clusters that appear random in shape and spatial distribution but carry class dependent information in shape and texture. Automated pattern recognition techniques are challenged because of changes in location, size and orientation of these clusters. Higher order spectral invariant features provide robustness to such transformations and are suited for texture and shape dependent information extraction from noisy images. In this work, the effectiveness of bispectral invariant features in diagnostic classification of breast thermal images into malignant, benign and normal classes is evaluated and a phase-only variant of these features is proposed. High resolution IR images of breasts, captured with measuring accuracy of ±0.4% (full scale) and temperature resolution of 0.1 °C black body, depicting malignant, benign and normal pathologies are used in this study. Breast images are registered using their lower boundaries, automatically extracted using landmark points whose locations are learned during training. Boundaries are extracted using Canny edge detection and elimination of inner edges. Breast images are then segmented using fuzzy c-means clustering and the hottest regions are selected for feature extraction. Bispectral invariant features are extracted from Radon projections of these images. An Adaboost classifier is used to select and fuse the best features during training and then classify unseen test images into malignant, benign and normal classes. A data set comprising 9 malignant, 12 benign and 11 normal cases is used for evaluation of performance. Malignant cases are detected with 95% accuracy. A variant of the features using the normalized bispectrum, which discards all magnitude information, is shown to perform better for classification between benign and normal cases, with 83% accuracy compared to 66% for the original.

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A nanostructured Schottky diode was fabricated to sense hydrogen and propene gases in the concentration range of 0.06% to 1%. The ZnO sensitive layer was deposited on SiC substrate by pulse laser deposition technique. Scanning electron microscopy and X-ray diffraction characterisations revealed presence of wurtzite structured ZnO nanograins grown in the direction of (002) and (004). The nanostructured diode was investigated at optimum operating temperature of 260 °C. At a constant reverse current of 1 mA, the voltage shifts towards 1% hydrogen and 1% propene were measured as 173.3 mV and 191.8 mV, respectively.

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The Flightless Cormorant Phalacrocorax harrisi is restricted to c. 400 km of the western coastline of the Galápagos archipelago coinciding with the local occurrence of seasonal upwelling of oceanic currents. Individuals frequently make more than one breeding attempt per year, usually change mates, and when juveniles are raised, females desert them to the further care of their mates who complete the rearing alone. Here we report data from a ten-year historical study of a colony stretching c.2 km along the coast-line and representing c. 12% of the total population of the species. The number of clutches laid and juveniles fledged were linked to the occurrence of cold water in off-shore foraging grounds. Most Flightless Cormorants have attachments to local stretches of coastline several hundred metres long. However, a few birds travelled many kilometres, including between colonies, sometimes over open sea. We show that males invest more in nest-building and feeding of the offspring than their mates, and we relate this to the (presumed) in-bred nature of the colony and to male and female reproductive strategies. Our data validate a published demographic model of the species (Valle 1995).

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We investigated the influence of rectal temperature on the immune system during and after exercise. Ten well-trained male cyclists completed exercise trials (90 min cycling at 60% VO(2max) + 16.1 - km time trial) on three separate occasions: once in 18 degrees C and twice in 32 degrees C. Twenty minutes after the trials in 32 degrees C, the cyclists sat for approximately 20 min in cold water (14 degrees C) on one occasion, whereas on another occasion they sat at room temperature. Rectal temperature increased significantly during cycling in both conditions, and was significantly higher after cycling in 32 degrees C than in 18 degrees C (P < 0.05). Leukocyte counts increased significantly during cycling but did not differ between the conditions. The concentrations of serum interleukin (IL)-6, IL-8 and IL-10, plasma catecholamines, granulocyte-colony stimulating factor, myeloperoxidase and calprotectin increased significantly following cycling in both conditions. The concentrations of serum IL-8 (25%), IL-10 (120%), IL-1 receptor antagonist (70%), tumour necrosis factor-alpha (17%), plasma myeloperoxidase (26%) and norepinephrine (130%) were significantly higher after cycling in 32 degrees C than in 18 degrees C. During recovery from exercise in 32 degrees C, rectal temperature was significantly lower in response to sitting in cold water than at room temperature. However, immune changes during 90 min of recovery did not differ significantly between sitting in cold water and at room temperature. The greater rise in rectal temperature during exercise in 32 degrees C increased the concentrations of serum IL-8, IL-10, IL-1ra, TNF-alpha and plasma myeloperoxidase, whereas the greater decline in rectal temperature during cold water immersion after exercise did not affect immune responses.

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The health impacts of exposure to ambient temperature have been drawing increasing attention from the environmental health research community, government, society, industries, and the public. Case-crossover and time series models are most commonly used to examine the effects of ambient temperature on mortality. However, some key methodological issues remain to be addressed. For example, few studies have used spatiotemporal models to assess the effects of spatial temperatures on mortality. Few studies have used a case-crossover design to examine the delayed (distributed lag) and non-linear relationship between temperature and mortality. Also, little evidence is available on the effects of temperature changes on mortality, and on differences in heat-related mortality over time. This thesis aimed to address the following research questions: 1. How to combine case-crossover design and distributed lag non-linear models? 2. Is there any significant difference in effect estimates between time series and spatiotemporal models? 3. How to assess the effects of temperature changes between neighbouring days on mortality? 4. Is there any change in temperature effects on mortality over time? To combine the case-crossover design and distributed lag non-linear model, datasets including deaths, and weather conditions (minimum temperature, mean temperature, maximum temperature, and relative humidity), and air pollution were acquired from Tianjin China, for the years 2005 to 2007. I demonstrated how to combine the case-crossover design with a distributed lag non-linear model. This allows the case-crossover design to estimate the non-linear and delayed effects of temperature whilst controlling for seasonality. There was consistent U-shaped relationship between temperature and mortality. Cold effects were delayed by 3 days, and persisted for 10 days. Hot effects were acute and lasted for three days, and were followed by mortality displacement for non-accidental, cardiopulmonary, and cardiovascular deaths. Mean temperature was a better predictor of mortality (based on model fit) than maximum or minimum temperature. It is still unclear whether spatiotemporal models using spatial temperature exposure produce better estimates of mortality risk compared with time series models that use a single site’s temperature or averaged temperature from a network of sites. Daily mortality data were obtained from 163 locations across Brisbane city, Australia from 2000 to 2004. Ordinary kriging was used to interpolate spatial temperatures across the city based on 19 monitoring sites. A spatiotemporal model was used to examine the impact of spatial temperature on mortality. A time series model was used to assess the effects of single site’s temperature, and averaged temperature from 3 monitoring sites on mortality. Squared Pearson scaled residuals were used to check the model fit. The results of this study show that even though spatiotemporal models gave a better model fit than time series models, spatiotemporal and time series models gave similar effect estimates. Time series analyses using temperature recorded from a single monitoring site or average temperature of multiple sites were equally good at estimating the association between temperature and mortality as compared with a spatiotemporal model. A time series Poisson regression model was used to estimate the association between temperature change and mortality in summer in Brisbane, Australia during 1996–2004 and Los Angeles, United States during 1987–2000. Temperature change was calculated by the current day's mean temperature minus the previous day's mean. In Brisbane, a drop of more than 3 �C in temperature between days was associated with relative risks (RRs) of 1.16 (95% confidence interval (CI): 1.02, 1.31) for non-external mortality (NEM), 1.19 (95% CI: 1.00, 1.41) for NEM in females, and 1.44 (95% CI: 1.10, 1.89) for NEM aged 65.74 years. An increase of more than 3 �C was associated with RRs of 1.35 (95% CI: 1.03, 1.77) for cardiovascular mortality and 1.67 (95% CI: 1.15, 2.43) for people aged < 65 years. In Los Angeles, only a drop of more than 3 �C was significantly associated with RRs of 1.13 (95% CI: 1.05, 1.22) for total NEM, 1.25 (95% CI: 1.13, 1.39) for cardiovascular mortality, and 1.25 (95% CI: 1.14, 1.39) for people aged . 75 years. In both cities, there were joint effects of temperature change and mean temperature on NEM. A change in temperature of more than 3 �C, whether positive or negative, has an adverse impact on mortality even after controlling for mean temperature. I examined the variation in the effects of high temperatures on elderly mortality (age . 75 years) by year, city and region for 83 large US cities between 1987 and 2000. High temperature days were defined as two or more consecutive days with temperatures above the 90th percentile for each city during each warm season (May 1 to September 30). The mortality risk for high temperatures was decomposed into: a "main effect" due to high temperatures using a distributed lag non-linear function, and an "added effect" due to consecutive high temperature days. I pooled yearly effects across regions and overall effects at both regional and national levels. The effects of high temperature (both main and added effects) on elderly mortality varied greatly by year, city and region. The years with higher heat-related mortality were often followed by those with relatively lower mortality. Understanding this variability in the effects of high temperatures is important for the development of heat-warning systems. In conclusion, this thesis makes contribution in several aspects. Case-crossover design was combined with distribute lag non-linear model to assess the effects of temperature on mortality in Tianjin. This makes the case-crossover design flexibly estimate the non-linear and delayed effects of temperature. Both extreme cold and high temperatures increased the risk of mortality in Tianjin. Time series model using single site’s temperature or averaged temperature from some sites can be used to examine the effects of temperature on mortality. Temperature change (no matter significant temperature drop or great temperature increase) increases the risk of mortality. The high temperature effect on mortality is highly variable from year to year.

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Exposure to cold air, whole body cryotherapy (WBC), is a novel treatment employed by athletes. In WBC individuals dressed in minimal clothing are exposed to a temperature below -100°C for 2-4 min. The use of WBC has been advocated as a treatment for various knee injuries. PURPOSE: To compare the effects of two modalities of cryotherapy, -110°C WBC and 8°C cold water immersion (CWI) on knee skin temperature (Tsk). METHODS: With ethical approval and written informed consent 10 healthy active male participants (26.5±4.9 yr, 183.5±6.0 cm, 90.7±19.9 kg, 26.8±5.0 kg/m2, 23.0±9.3% body fat (measured by DXA), 7.6 ± 2.0 mm patellar skin fold; mean±SD) were exposed to 4 min of CWI and WBC. The treatment order was randomised in a controlled crossover design, with a minimum of 7 days between treatments. During WBC participants stood in a chamber (-60±3°C) for 20 s before entering the main chamber (-110°C±3°C) where they remained for 3 min and 40 s. For CWI participants were seated in a tank filled with cold water (8±0.3°C) and immersed to the level of the sternum for 4 min. Right knee Tsk was assessed via non-contact, infrared thermal imaging. A quadrilateral region of interest was created using inert markers placed 5 cm above and below the most superior and inferior aspect of the patella. Tsk within this quadrilateral was recorded pre, immediately post and every 10 min thereafter for 60 min. Tsk changes were examined using a two-way (treatment x time) repeated measures analyses of variance. In addition, a paired sample t-test was used to compare baseline Tsk before both treatments. RESULTS: Knee Tsk was similar before treatment (WBC: 29.9±0.7°C, CWI: 29.6±0.9°C, p>0.05). There was a significant main effect for treatment (p<0.05) and time (p<0.001). Compared to baseline, Tsk was significantly reduced (p<0.05) immediately post and at 10, 20, 30, 40, 50 and 60 min after both cooling modalities. Knee Tsk was lower (p<0.05) immediately after WBC (19.0±0.9°C) compared to CWI (20.5±0.6°C). However, from 10 to 60 min post, knee Tsk was lower (p<0.05) following the CWI treatment. CONCLUSION: WBC elicited a greater decrease in knee Tsk compared to CWI immediately after treatment. However, both modalities display different recovery patterns and Tsk after CWI was significantly lower than WBC at 10, 20, 30, 40, 50 and 60 min after treatment.

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Homologous recombination repair (HRR) is required for both the repair of DNA double strand breaks (DSBs) and the maintenance of the integrity of DNA replication forks. To determine the effect of a mutant allele of the RAD51 paralog XRCC2 (342delT) found in an HRR-defective tumour cell line, 342delT was introduced into HRR proficient cells containing a recombination reporter substrate. In one set of transfectants, expression of 342delT conferred sensitivity to thymidine and mitomycin C and suppressed HRR induced at the recombination reporter by thymidine but not by DSBs. In a second set of transfectants, the expression of 342delT was accompanied by a decreased level of the full-length XRCC2. These cells were defective in the induction of HRR by either thymidine or DSBs. Thus 342delT suppresses recombination induced by thymidine in a dominant negative manner while recombination induced by DSBs appears to depend upon the level of XRCC2 as well as the expression of the mutant XRCC2 allele. These results suggest that HRR pathways responding to stalled replication forks or DSBs are genetically distinguishable. They further suggest a critical role for XRCC2 in HRR at replication forks, possibly in the loading of RAD51 onto gapped DNA.

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Background WSUD implementation in the Gold Coast City Council area commenced more than a decade ago. As a result, Council is expected to be in possession of WSUD assets valued at over tens of million dollars. The Gold Coast City Council is responsible for the maintenance and long-term management of these WSUD assets. Any shortcoming in implementation of best WSUD practices can potentially result in substantial liabilities and ineffective expenditure for the Council in addition to reduced efficiencies and outcomes. This highlights the importance of periodic auditing of WSUD implementation. Project scope The overall study entailed the following tasks: * A state-of-the-art literature review of the conceptual hydraulic and water quality treatment principles, current state of knowledge in relation to industry standards, best practice and identification of knowledge gaps in relation to maintenance and management practices and potential barriers to the implementation of WSUD. * Council stakeholder interviews to understand current practical issues in relation to the implementation of WSUD and the process of WSUD application from development application approval to asset management. * Field auditing of selected WSUD systems for condition assessment and identification of possible strengths and weaknesses in implementation. * Review of the Land Development Guidelines in order to identify any gaps and to propose recommendations for improvement. Conclusions Given below is a consolidated summary of the findings of the study undertaken. State-of-the-art literature review Though the conceptual framework for WSUD implementation is well established, the underlying theoretical knowledge underpinning the treatment processes and maintenance regimes and life cycle costing are still not well understood. Essentially, these are the recurring themes in the literature, namely, the inadequate understanding of treatment processes and lack of guidance to ensure specificity of maintenance regimes and life cycle costing of WSUDs. The fundamental barriers to successful WSUD implementation are: * Lack of knowledge transfer – This essentially relates to the lack of appropriate dissemination of research outcomes and the common absence of protocols for knowledge transfer within the same organisation. * Cultural barriers – These relate to social and institutional factors, including institutional inertia and the lack of clear understanding of the benefits. * Fragmented responsibilities – This results from poor administrative integration within local councils in relation to WSUDs. * Technical barriers – These relate to lack of knowledge on operational and maintenance practices which is compounded by model limitations and the lack of long-term quantitative performance evaluation data. * Lack of engineering standards – Despite the availability of numerous guidelines which are non-enforceable and can sometimes be confusing, there is a need for stringent engineering standards. The knowledge gaps in relation to WSUDs are only closing very slowly. Some of the common knowledge gaps identified in recent publications have been recognised almost a decade ago. The key knowledge gaps identified in the published literature are: * lack of knowledge on operational and maintenance practices; * lack of reliable methodology for identifying life cycle issues including costs; * lack of technical knowledge on system performance; * lack of guidance on retrofitting in existing developments. Based on the review of barriers to WSUD implementation and current knowledge gaps, the following were identified as core areas for further investigation: * performance evaluation of WSUD devices to enhance model development and to assess their viability in the context of environmental, economic and social drivers; establishing realistic life cycle costs to strengthen maintenance and asset management practices; * development of guidelines specific to retrofitting in view of the unique challenges posed by existing urban precincts together with guidance to ensure site specificity; establishment of a process for knowledge translation for enhancing currently available best practice guidelines; * identification of drivers and overcoming of barriers in the areas of institutional fragmentation, knowledge gaps and awareness of WSUD practices. GCCC stakeholder interviews Fourteen staff members involved in WSUD systems management in the Gold Coast City Council, representing four Directorates were interviewed using a standard questionnaire. The primary issues identified by the stakeholders were: * standardisation of WSUD terminology; * clear protocols for safeguarding devices during the construction phase; * engagement of all council stakeholders in the WSUD process from the initial phase; * limitations in the Land Development Guidelines; * ensuring public safety through design; * system siting to avoid conflicts with environmental and public use of open space; * provision of adequate access for maintenance; * integration of social and ecosystem issues to ensure long-term viability of systems in relation to both, vandalism and visual recreation; * lack of performance monitoring and inadequacy of the maintenance budget; * lack of technical training for staff involved in WSUD design approvals and maintenance; incentives for developers for acting responsibly in stormwater management. Field auditing of WSUD systems A representative cross section of WSUD systems in the Gold Coast were audited in the field. The following strengths and weaknesses in WSUD implementation were noted: * The implementation of WSUD systems in the field is not consistent. * The concerns raised by the stakeholders during the interviews in relation to WSUD implementation was validated from the observations from the field auditing, particularly in relation to the following: * safeguarding of devices during the construction phase * public safety * accessibility for maintenance * lack of performance monitoring by Council to assess system performance * inadequate maintenance of existing systems to suit site specific requirements. * A treatment train approach is not being consistently adopted. * Most of the systems audited have satisfactorily catered for public safety. Accessibility for maintenance has been satisfactorily catered for in most of the systems that were audited. * Systems are being commissioned prior to construction activities being substantially completed. * The hydraulic design of most systems appears to be satisfactory. * The design intent of the systems is not always clear. Review of Land Development Guidelines The Land Development Guidelines (TDG) was extensively reviewed and the following primary issues were noted in relation to WSUD implementation: * the LDG appears to have been prepared primarily to provide guidance to developers. It is not clear to what extent the guidelines are applicable to Council staff involved in WSUD maintenance and management; * Section 13 is very voluminous and appears to be a compilation of a series of individual documents resulting in difficulties in locating specific information, a lack of integration and duplication of information; * the LDG has been developed with a primary focus on new urban precinct development and the retrofitting of systems in existing developments has not been specifically discussed; * WSUDs are discussed in two different sections in the LDG and it is not clear which section takes precedence as there are inconsistencies between the two sections; there is inconsistent terminology being used; * there is a need for consolidation of information provided in different sections in the LDG; * there are inconsistencies in the design criteria provided; * there is a need for regular updating of the LDG to ensure that the information provided encompasses the state-of-the-art; * there is limited guidance provided for the preparation of maintenance plans and life cycle costing to assist developers in asset handover and to assist Council staff in assessment. * Based on these observations, eleven recommendations have been provided which are discussed below. Additionally, the stakeholder provided the following specific comments during the interviews in relation to the LDG: * lack of flexibility to cover the different stages of the life cycle of the systems; * no differentiation in projects undertaken by developers and Council; * inadequate information with regards to safety issues such as maximum standing water depth, fencing and safety barriers and public access; * lack of detailed design criteria in relation to Crime Prevention through Environmental Design, safety, amenity, environment, surrounding uses and impacts on surroundings; * inadequate information regarding maintenance requirements specific to the assessment and compliance phases; * recommendations for plantings are based primarily on landscape requirements rather than pollutant uptake capability. Recommendations With regards to the Land Development Guidelines, the following specific recommendations are provided: 1. the relevant sections and their extent of applicability to Council should be clearly identified; 2. integration of the different subsections within Section 13 and re-formatting the document for easy reference; 3. the maintenance guidelines provided in Section 13 should be translated to a maintenance manual for guidance of Council staff; 4. should consider extending the Guidelines to specifically encompass retrofitting of WSUD systems to existing urban precincts; 5. Section 3 needs to be revised to be made consistent with Section 13, to ensure priority for WSUD practices in urban precincts and to move away from conventional stormwater drainage design such as kerb and channelling; 6. it would also be good to specify as to which Section takes predominance in relation to stormwater drainage. It is expected that Section 13 would take predominance over the other sections in the LDG; 7. terminology needs to be made consistent to avoid confusion among developers and Council staff. Water Sensitive Urban Design is the term commonly used in Australia for stormwater quality treatment, rather than Stormwater Quality Improvement Devices. This once again underlines the need for ensuring consistency between Section 3 and Section 13; 8. it would also be good if there is a glossary of commonly used terms in relation to WSUD for use by all stakeholders and which should also be reflected in the LDG; 9. consolidation of all WSUD information into one section should be considered together with appropriate indicators in other LDG Sections regarding the availability of WSUD information. Ensuring consistency in the information provided is implied; 10. Section 13 should be updated at regular intervals to ensure the incorporation of the latest in research outcomes and incorporating criteria and guidance based on the state-of-the-art knowledge. The updating could be undertaken, say, in five year cycles. This would help to overcome the current lack of knowledge transfer; 11. the Council should consider commissioning specialised studies to extend the current knowledge base in relation to WSUD maintenance and life cycle costing. Additionally, Recommendation 10 is also applicable in this instance. The following additional recommendations are made based on the state-of-the-art literature review, stakeholder interviews and field auditing of WSUD systems: 1. Performance monitoring of existing systems to assess improvements to water quality, identify modifications and enhancements to improve performance; 2. Appropriate and monitored maintenance during different phases of development of built assets over time is needed to investigate the most appropriate time/phase of development to commission the final WSUD asset. 3. Undertake focussed investigations in the areas of WSUD maintenance and asset management in order to establish more realistic life cycle costs of systems and maintenance schedules; 4. the engagement of all relevant Council stakeholders from the initial stage of concept planning through to asset handover, and ongoing monitoring. This close engagement of internal stakeholders will assist in building a greater understanding of responsibilities and contribute to overcoming constraints imposed by fragmented responsibilities; 5. the undertaking of a public education program to inform the community of the benefits and ecosystem functions of WSUD systems; 6. technical training to impart state-of-the-art knowledge to staff involved in the approval of designs and maintenance and management of WSUD projects; 7. during the construction phase, it is important to ensure that appropriate measures to safeguard WSUD devices are implemented; 8. risks associated with potential public access to open water zones should be minimised with the application of appropriate safety measures; 9. system siting should ensure that potential conflicts are avoided with respect to public and ecosystem needs; 10. integration of social and ecosystem issues to ensure long-term viability of systems; provide incentives to developers who are proactive and responsible in the area of stormwater management.