Engineering an Anti‐Graffiti System: A Study in Industrial Product Design

The objective of this work was to develop products for the anti‐graffiti market using a product design framework that takes into account the company core practices and meets customer expectations. Product development comprised several concurrent steps including market research and analysis to determine the market potential using a Quality Functional Deployment tool. From market research it was estimated that anti‐graffiti products had significant potential within Australia. A range of technical and quality parameters were tested. The Hildebrand and Hansen solubility parameters, viscosity and diffusivity estimates were mainly used for technical evaluation of products. An iterative process was used throughout in conjunction with parameter restraints to meet environmental sustainability, waste reduction and minimize resource consumption. The result was a cost effective product, tailored to customer expectations.     

High-power long-wavelength (λ~11.5 μm) quantum cascadelasers operating above room temperature

High-temperature operation (T=320 K) of quantum cascade lasers has been extended to 11.5-μm wavelengths with high performances. Peak-pulsed optical power of 55 mW is obtained at 300 K with a high T ₀=172 K, in good agreement with our theoretical model     

A randomized double-blind comparison of the effects on systemic calcium homeostasis of topical calcitriol (3 micrograms/g) and calcipotriol (50 micrograms/g) in the treatment of chronic plaque psoriasis vulgaris

Calcitriol and calcipotriol are effective treatments for psoriasis, although the two have never been directly compared. We compared the efficacy and toxicity of each agent in 24 patients with moderately extensive chronic plaque psoriasis, who were randomized in double-blind fashion to apply 90 g per week of either calcitriol (3 micrograms/g) ointment or calcipotriol (50 micrograms/g) ointment over an 8-week period. Mean PASI in patients applying calcitriol fell from 13 to 8.8 (p < 0.05) and in patients applying calcipotriol from 14.9 to 4.7 (p < 0.005). The reduction was significantly greater in the calcipotriol-treated group (p < 0.05). There was a small increase in serum ionized calcium in the calcipotriol-treated group (from 1.21 mmol/L to 1.25 mmol/L, p < 0.05) but no effect on calcium homeostasis in the calcitriol group.     

Intracavitary ultrasound phased arrays for prostate thermal therapies: MRI compatibility and in vivo testing

A 62 element MRI-compatible linear phased array was designed and constructed to investigate the feasibility of using transrectal ultrasound for the thermal therapeutic treatment of prostate cancer and benign prostatic hyperplasia. An aperiodic design technique developed in a previous study was used in the design of this array, which resulted in reduced grating lobe levels by using an optimized random distribution of unequally sized elements. The element sizes used in this array were selected to be favorable for both grating lobe levels as determined by array aperiodicity and array efficiency as determined by width to thickness ratios. The heating capabilities and MRI compatibility of the array were tested with in vivo rabbit thigh muscle heating experiments using MRI temperature monitoring. The array produced therapeutic temperature elevations in vivo at depths of 3-6 cm and axial locations up to 3 cm off the central axis and increased the size of the heated volume with electronic scanning of a single focus. The ability of this array to be used for ultrasound surgery was demonstrated by creating necrosed tissue lesions in vivo using short high-power sonications. The ability of the array to be used for hyperthermia was demonstrated by inducing therapeutic temperature elevations for longer exposures. Based on the acoustic and heating performance of this array, it has the potential to be clinically useful for delivering thermal therapies to the prostate and other target volumes close to body cavities.     

Hyperexpression of epidermal growth factor receptors in granulosa cells from women with polycystic ovary syndrome

We report the characterization of two distinct binding sites with receptor characteristics for leukotriene (LT)D4 and LTC4 in membranes from human lung parenchyma. The use of S-decyl-glutathione allowed us to characterize a previously unidentified high affinity binding site for LTC4. Computerized analysis of binding data revealed that each leukotriene interacts with two distinct classes of binding sites (Kd = 0.015 and 105 nM for LTC4 and 0.023 and 230 nM for LTD4) and that despite cross-reactivity, the two high affinity sites are different entities. LTD4 binding sites displayed features of G protein-coupled receptors, whereas LTC4 binding sites did not show any significant modulation by guanosine-5'-(beta, gamma-imido)triphosphate or stimulation of GTPase activity. The antagonists ICI 198,615 and SKF 104353 were unselective for the high and low affinity states of LTD4 receptor, whereas only SKF 104353 was able to recognize the two [3H]LTC4 binding sites although with different affinities. These data indicate that in human lung parenchyma, LTD4 and LTC4 recognize two different binding sites; these binding sites are different entities; and for LTD4, the two binding sites represent the interconvertible affinity states of a G protein-coupled receptor, whereas for LTC4, the high affinity site is likely to be a specific LTC4 receptor.     

Estimating Winter Streamflow Using Conceptual Streamflow Model

Ice-affected periods represent a significant portion of the annual hydrograph for most Canadian hydrometric stations. Because the stage-discharge relation is not reliable under ice-cover conditions, Water Survey of Canada subjectively interpolates winter streamflow from as few as two observations of discharge during the ice-covered season, which may last 6 months or longer. An alternative method of producing discharge estimates is proposed that uses a combination of conceptual and statistical hydrological modeling to overcome limitations in both the availability of data and our understanding of relevant processes. A conceptual hydrological model is tested to evaluate the utility of this approach for data-sparse regions. When model predictions were adjusted to fit two winter measurements, 79% of all verification measurements were within 20% of predicted estimates. There was a seasonal bias to the error distribution, with most measurements within the first 30 days after freeze-up being less than predicted and most measurements after April 1 being greater than predicted. These deviations probably result from hydraulic and hydrologic processes not represented within the model.