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1.
Toronto is a rare global city because negotiating public land ownership remains a defining feature of the city's urban politics. The awarding of the 2015 Pan American Games to Toronto is a prime occasion to witness how fragmented governance can limit the ambition and enthusiasm of a sporting mega‐event. Historically, Toronto has not been known for its ability to host large‐scale sporting events but it has recently used a series of failed Olympic bids and smaller sporting events to trigger piecemeal “legacy” development. In this article we argue that the awarding of the Pan American Games to Toronto was predicated on a process that removed local politics from the bidding process. Focusing on the development of the athletes’ village in the West Don Lands and incorporating a number of interviews with key stakeholders across Toronto, this research illustrates that the heavy involvement and investment of the Province of Ontario in the Pan American spectacle forces us to ask: Whose waterfront? Whose games?  相似文献   
2.
A Model Reference Adaptive Control (MRAC) system is evaluated via hybrid computer simulation and experimental application to a computer-controlled, pilot plant evaporator. In both the simulation and experimental studies, the MRAC system performed well and was insensitive to unmeasured process disturbances, to the choice of the initial control policy and to changes in plant operating conditions. In addition to providing an algorithm for adapting control systems to accommodate changing process parameters, MRAC also provides a systematic approach for tuning or developing multivariable control systems for time-invariant processes.  相似文献   
3.
This report summarises the main findings of a series of three studies conducted by the centre d'Economie des Ressources Naturelles (CERNA) into strategies adopted by mining and metallurgical companies in the industrialised countries.  相似文献   
4.
SURVIVAL OF VIBRIO VULNIFICUS AT REDUCED TEMPERATURES AND ELEVATED NUTRIENT   总被引:1,自引:0,他引:1  
Studies were conducted on the survival of the human bacterial pathogen, Vibrio vulnificus, in heart infusion broth held at 5, 10 and 15°C. Culturability was monitored by plate counts on heart infusion agar, and viability by examination of electron transport activity. Whereas V. vulnificus demonstrated growth at 15°C, a rapid loss of culturability for cells held at the lower temperatures was observed. At all temperatures, however, a significant portion of the population was found to remain viable over the 28 day study period. The ability of V. vulnificus cells to metabolize exogenously supplied nutrient at reduced temperatures was also examined as an indicator of viability. Cells were able to rapidly take up and respire mixed amino acids at 9 and 13°C, whereas cells incubated at 2°C showed relatively little metabolism of the labeled substrates. Like the growth and viability study, the radiotracer study indicates survival of V. vulnificus at reduced temperatures, although with reduced rates of activity. The possible implications of these findings for the transport and storage of shellfish is discussed.  相似文献   
5.
DETECTION OF THE VIABLE BUT NONCULTURABLE STATE IN ESCHERICHIA COLI O157:H7   总被引:2,自引:0,他引:2  
Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is recognized as a frequent cause of gastroenteritis ranging from mild to severe bloody diarrhea. The Shiga-like toxin produced by EHEC can result in hemolytic uremic syndrome, now the major cause of acute kidney failure in children in the United States. Inadequately cooked beef is most commonly implicated in the transmission of EHEC, although only a small fraction of cattle appear to harbor the organism. In several studies EHEC positive herds were detected only in the summer months correlating with the occurrence of human infections. Numerous E. coli strains have been shown to enter a viable but nonculturable (VBNC) state as a result of environmental stresses, including low temperature. Using traditional plating methods and the BacLight Molecular Probe, we monitored EHEC strains incubated in river water (RW) and artificial sea water (ASW) at temperatures of 5C and 25C for their entry into the VBNC state. EHEC strains remained culturable for over 40 days in both ASW and RW incubated at 25C. In ASW, these levels were higher than a non-EHEC control. At 5C, the number of culturable EHEC cells dropped gradually in both RW and ASW. Using the BacLight Molecular Probe, we were able to demonstrate that these cells, though not culturable, were viable indicating entry into the VBNC state. Our study suggests that temperature and not salinity is the primary signal for entry into this state .  相似文献   
6.
The lysosomal enzyme acid phosphatase has been characterized and quantified in tapestrip biopsies of human stratum corneum by means of a sensitive spectrofluorometric procedure. When the stratum corneum of panellists was exposed to dilute solutions of various surfactants under realistic exposure conditions, the changes observed in stratum corneum acid phosphatase specific activity have been found to correlate very closely with the visual, macroscopic changes such as dryness and flakiness, that are elicited in skin as a result of surfactants. This method monitors denaturation of stratum corneum proteins, which is an important feature of skin surfactant interactions, and serves as an effective, non-invasive predictive tool for skin irritancy and mildness of surfactants.
Prevention et mesure de l'action des tensio-actifs sur la peau humaine dans des conditions conformes a la réalité  相似文献   
7.
This paper proposes a new nonparametric spectral density estimator for time series models with general autocorrelation. The conventional nonparametric estimator that uses a positive kernel has mean squared error no better than n?4/5. We show that the best implementation of our estimator has mean squared error of order n?8/9, provided there is sufficient smoothness present in the spectral density. This is, of course, achieved by bias reduction; however, unlike most other bias reduction methods, like the kernel method with higher‐order kernels, our procedure ensures a positive definite estimate. Our method is a generalization of the well‐known prewhitening method of spectral estimation; we argue that this can best be interpreted as multiplicative bias reduction. Higher‐order expansions for the proposed estimator are derived, providing an improved bandwidth choice that minimizes the mean squared error to the second order. A simulation study shows that the recommended prewhitened kernel estimator reduces bias and mean squared error in spectral density estimation.  相似文献   
8.
Synchrotron‐generated X‐rays provide scientists with a multitude of investigative techniques well suited for the analysis of the composition and structure of all types of materials and specimens. Here, we describe the properties of synchrotron‐generated X‐rays and the advantages that they provide for qualitative morphological research of millimetre‐sized biological organisms and biomaterials. Case studies of the anatomy of insect heads, of whole microarthropods and of the three‐dimensional reconstruction of the cuticular tendons of jumping beetles, all performed at the beamline ID19 of the European Synchrotron Radiation Facility (ESRF), are presented to illustrate the techniques of phase‐contrast tomography available for anatomical and structural investigations. Various sample preparation techniques are described and compared and experimental settings that we have found to be particularly successful are given. On comparing the strengths and weaknesses of the technique with traditional histological thin sectioning, we conclude that synchrotron radiation microtomography has a great potential in biological microanatomy.  相似文献   
9.
Properties of the fiber/matrix interface in a SiC/glass-ceramic composite were investigated using an indentation method in Which a pyramidal indenter is used to push on the fibers and cause sliding at the interface. An ultralow-load indentation instrument was used to measure force and displacement continuously during loading, unloading, and load cycling. Frictional sliding and combined debonding/frictional sliding at the interface were analyzed. The analyses enabled the results to be used to provide a measure of the debond fracture energy, the magnitude of the frictional sliding stress, a measure of the uniformity of the frictional stress, and an indication of the sensitivity of the frictional stress to repeated sliding, varying load rate, and exposure to high temperatures.  相似文献   
10.
Samples of twenty-five different cultivars of potatoes were prepared and examined after cooking by boiling and by pressure cooking, peeled and 'in the jacket' in a factorial design to study the effect of cooking on dietary fibre fractions of potatoes. Raw samples were prepared as control.
The samples were analysed for acid detergent fibre (ADF) and lignin by published procedures. Filtration problems were encountered with the published procedure for neutral detergent fibre (NDF) giving rise to lack of reproducibility. Reproducibility was restored by introducing a short incubation of the sample with α-amylase enzyme ( Bacillus subtilis ) prior to the normal detergent digestion.
The lignin content of all samples was < 0.25% on a dry matter basis. Both ADF and NDF increased on cooking but boiled samples did not differ from pressure cooked samples. Cooking 'in the jacket' gave higher ADF values than peeled samples but the effect was not observed for NDF values.
Cultivar differences were significant for both ADF and NDF values but as the samples were all from a single season's crop in a single field a definitive ranking is not possible.  相似文献   
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