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11.
With increases in storm frequency and intensity, municipalities are finding new ways of managing stormwater. Solutions require collaboration across planning disciplines and input from an informed public. This study compares a system of bioswales to existing curb and gutter infrastructure in a post-industrial streetscape of Hamilton, Ontario. Using the geodesign process, a section of Ottawa St. North was modelled to show how green infrastructure can ease the burden on aging, combined sewer systems. Qualitative data was gathered from residents of the neighbourhood through field notes, and quantitative geospatial data through GIS. Parametric modelling was used to generate a design, and scenarios created to show resulting impacts on stormwater run-off. The model was posted online as an interactive presentation, accessible to all stakeholders for review and comment. The results of the study demonstrate powerful new tools that can assist landscape architects in designing, collaborating and communicating stormwater strategies. 相似文献
12.
Recent studies have yielded evidence that plant flavonoids reduce hepatic lipid and apolipoprotein B (apoB) secretion. However,
the possible role of flavonoids in regulating lipid and apoB secretion by the intestine has not been studied. The purpose
of our study was to examine the effects of quercetin, a common dietary flavonoid, on TAG and apoB secretion in a human intestinal
cell-line, CaCo-2. Differentiated postconfluent CaCo-2 cells grown on filters and pretreated with quercetin for 8 h were shown
by ELISA to inhibit basolateral apoB secretion in a dose-dependent manner. At 15 μM, the secretion of both apoB-100 and apoB-48
were inhibited similarly. This effect was shown to be specific, as quercetin did not affect the incorporation of [35S]methionine/cysteine into secreted TCA-precipitable proteins. To determine the mechanism underlying this inhibitory effect,
we examined two regulatory points: IAG availability and lipid transfer to the lipoprotein particle. Quercetin inhibited TAG
synthesis under both basal and lipid-rich conditions, indicating that lipid availability is a determining factor in the regulation
of apoB secretion by quercetin. The reduction was due at least in part to a decrease in diacylglycerol acyltransferase activity.
We next examined lipid transfer or lipidation of the lipoprotein particle by analyzing microsomal IAG transfer protein (MTP)
activity. Quercetin decreased MTP activity moderately. In summary, the data demonstrated that pharmacological concentrations
of quercetin are a potent inhibitor of intestinal apoB secretion and that reduced lipid availability and lipidation in the
lipoprotein assembly step are the mechanism for the suppression of apoB-containing lipoprotein secretion by quercetin in CaCo-2
cells. 相似文献
13.
14.
Many two layer robot architectures have been proposed and implemented. While justification for the design can be well argued, how does one know it is really a good idea? In this paper, one describes a two layer architecture (reinforcement learning in the bottom layer and POMDP planning at the top) for a simulated robot and summarize a set of three experiments in which one evaluated the design. To address the many difficulties of evaluating robot architectures, one advocates an experimental approach in which design criteria are elucidated and then form the basis for the evaluation experiments. In our case, one tests the implementation for its reliability and generalization (our design criteria) by comparing our architecture to one in which a key component is substituted; in these experiments, one demonstrates significant performance gains on the design criteria for our architecture. 相似文献
15.
Our research addresses evaluating the usability of hypermedia systems o th offline (CD-ROMs) and online (Web) - and tries to capture the features that most characterize the specific nature of these systems. In this article, we describe an inspection technique that lets evaluators concentrate on the usability of specific aspects of hypermedia applications, such as information and navigation structuring, media integration and synchronization, and so on, without neglecting the surface aspects. Our technique uses operational guidelines, called abstract tasks (ATs), which systematically drive the inspection activities, allowing even less experienced evaluators to come up with valuable results. As they currently exist, we see ATs as evaluation patterns, which make it possible to maximize the reuse of an evaluator's expertise. That is, reuse takes advantage of previous work, thus reducing the effort to create a new one. ATs support the reuse of an evaluator's know-how. Their goal is to capture usability inspection expertise and to express it in a precise and understandable form, so that others can easily reproduce, communicate and exploit it. Our current work is devoted to extending the AT library to cover specific usability issues related to e-commerce Web sites 相似文献
16.
Two studies, 1 longitudinal and 1 cross-sectional, demonstrate that for young elementary school children, academic intrinsic motivation is a reliable, valid, and significant construct. It was positively related to achievement, IQ, and perception of competence, and inversely related to anxiety. Academic intrinsic motivation at age 9 was significantly predicted by motivation measured 1 and 2 years earlier, above and beyond the contribution of IQ and achievement. Children with higher academic intrinsic motivation at ages 7 and 8 were more likely to show higher motivation at age 9. Whereas young children could reliably distinguish between subject areas of academic intrinsic motivation, only math motivation showed consistently specific relations to other math criteria. Findings are discussed with regard to developmental theories of intrinsic motivation and the significance of academic intrinsic motivation for children's education. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
Anthocyanin composition and extractability in berry skin and wine of Vitis vinifera L. cv. Aglianico
Manfra M De Nisco M Bolognese A Nuzzo V Sofo A Scopa A Santi L Tenore GC Novellino E 《Journal of the science of food and agriculture》2011,91(15):2749-2755
BACKGROUND: The present article reports the anthocyanin content in the berry skin and wine of the Italian red grape cultivar Aglianico (clone VCR11 grafted onto 1103 Paulsen), one of the most ancient vines and famous for its deep‐red colour. Anthocyanins were extracted from frozen berry skin in an acidified methanol solution. The extraction mixtures, monitored for 120 h, were analysed by high‐performance liquid chromatography. RESULTS: The extraction from berry skin of delphinidin, petunidin and malvidin appeared to be a time‐independent process, whereas the concentration of peonidin increased linearly with time. Peonidin‐O‐acetyl‐glucoside was transferred from skin more slowly than petunidin‐O‐acetyl‐glucoside and malvidin‐O‐acetyl‐glucoside. The anthocyanin composition of the resulting wine showed that the total anthocyanin content was about one‐tenth of the corresponding berry skin content. The ratio acetyl/coumaroyl anthocyanins in the wine was sharply higher than the value in berry skin (0.85 and 0.10, respectively), indicating an enrichment of acetyl derivatives in the wine. CONCLUSION: Levels of single anthocyanins in wine were not always correlated with those detected in grapes, as they were affected by winemaking. The high values of some anthocyanins in Aglianico wine could ameliorate its quality, increasing the chromatic properties, aging stability and product acceptance. Copyright © 2011 Society of Chemical Industry 相似文献
18.
Zachary H. Levine Benjamin R. Galloway Adele P. Peskin 《Journal of research of the National Institute of Standards and Technology》2011,116(3):685-688
RECIST (Response Evaluation Criteria in Solid Tumors) is a linear measure intended to predict tumor size in medical computed tomography (CT). In this work, using purely geometrical considerations, we estimate how well RECIST can predict the volume of randomly-oriented tumor models, each composed of the union of ellipsoids. The principal conclusion is that RECIST is likely to work less well for realistic tumors than for ellipsoids. 相似文献
19.
Isolation of red wine components with anti-adhesion and anti-biofilm activity against Streptococcus mutans 总被引:1,自引:0,他引:1
Maria Daglia Monica Stauder Adele Papetti Caterina Signoretto Giovanni Giusto Pietro Canepari Carla Pruzzo Gabriella Gazzani 《Food chemistry》2010
Red wine is a widely consumed beverage with multiple beneficial effects on human health. In the present paper, the anticaries properties of red wine were studied in vitro and ex vivo. Our in vitro findings shows that dealcoholised red wine, besides exerting antibacterial activity, strongly interferes with Streptococcus mutans adhesion to saliva-coated hydroxyapatite (sHA) beads, promotes its detachment from sHA, and powerfully inhibits in vitro biofilm formation. The main components responsible for such activities were found to be proanthocyanidins. The ability of red wine to inhibit ex vivoS. mutans biofilm formation on the occlusal surface of natural human teeth also was demonstrated. 相似文献
20.
A Birkhoff interpolation problem is studied. The explicit solution and estimation of remainder is given. The cases of equidistant
and Chebyshev nodes are considered. This problem is of interest in collocation methods of boundary value problem (Costabile
and Napoli in Far East J. Appl. Math. 25(3):289–305, 2006; Costabile and Longo in Applied and Industrial Mathematics in Italy III, 2009, in press). In addition an application to quadrature is given. 相似文献