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51.
Spatial planning has been the subject of critique within the South African context, particularly the disconnect between the intentions of spatial plans and land use decision-making. The City of Cape Town uses a land use assessment mechanism called the Package of Plans, originally developed for the assessment of the Victoria and Alfred Waterfront development, which based on the hierarchical nature of the approach, can provide a link between strategic spatial planning and land use decision-making. Although the mechanism was developed for a specific purpose over 20 years ago, it has not been reviewed within the current spatial planning and land use legislative context. The paper reviews the Package of Plans within this current context and discusses the role it can play in linking spatial planning and land use management within the Cape Town context (and perhaps elsewhere). In so doing, it raises particular questions regarding the role of the mechanism within the City of Cape Town and ways its implementation could be improved. 相似文献
52.
Silke Corall Tamas Haraszti Tanja Bartoschik Joachim Pius Spatz Thomas Ludwig Elisabetta Ada Cavalcanti-Adam 《Computational Mechanics》2014,53(3):499-510
Cell migration is a crucial event for physiological processes, such as embryonic development and wound healing, as well as for pathological processes, such as cancer dissemination and metastasis formation. Cancer cell migration is a result of the concerted action of matrix metalloproteinases (MMPs), expressed by cancer cells to degrade the surrounding matrix, and integrins, the transmembrane receptors responsible for cell binding to matrix proteins. While it is known that cell-microenvironment interactions are essential for migration, the role of the physical state of such interactions remains still unclear. In this study we investigated human fibrosarcoma cell migration in two-dimensional (2D) and three-dimensional (3D) fibronectin (FN) microenvironments. By using antibody blocking approach and cell-binding site mutation, we determined that $\upalpha _{5}\upbeta _{1}$ -integrin is the main mediator of fibrosarcoma cell migration in 2D FN, whereas in 3D fibrillar FN, the binding of $\upalpha _{5}\upbeta _{1}$ - and $\upalpha _\mathrm{v}\upbeta _{3}$ -integrins is not necessary for cell movement in the fibrillar network. Furthermore, while the general inhibition of MMPs with GM6001 has no effect on cell migration in both 2D and 3D FN matrices, we observed opposing effect after targeted silencing of a membrane-bound MMP, namely MT1-MMP. In 2D fibronectin, silencing of MT1-MMP results in decreased migration speed and loss of directionality, whereas in 3D FN matrices, cell migration speed is increased and integrin-mediated signaling for actin dynamics is promoted. Our results suggest that the fibrillar nature of the matrix governs the migratory behavior of fibrosarcoma cells. Therefore, to hinder migration and dissemination of diseased cells, matrix molecules should be directly targeted, rather than specific subtypes of receptors at the cell membrane. 相似文献
53.
Elektronische Agenten können auf sämtlichen Stufen elektronischer Geschäftsprozesse eingesetzt werden, wodurch die Transaktionskosten gesenkt und der elektronische Geschäftsverkehr insgesamt beschleunigt und vereinfacht wird (vgl. [30], S. 548). 相似文献
54.
Natalija Dj Polovic Rada V Pjanovic Lidija M Burazer Sava J Velickovic Ratko M Jankov Tanja D Cirkovic Velickovic 《Journal of the science of food and agriculture》2009,89(1):8-14
BACKGROUND: It is thought that food sensitisers must be able to reach the intestine in order to sensitise patients. Pectin is a gel‐forming plant polysaccharide that can protect allergens from in vivo gastric digestion and in vitro pepsin digestion. The aim of this study was to examine if pectin gel formed in the acidic environment of the stomach can protect labile allergen from in vitro gastrointestinal digestion. RESULTS: Pectin forms a gel in the acidic conditions of gastric fluid up to a concentration of 1.0 ± 0.14 g L?1. Four allergenic fruits (kiwi, cherry, apple and banana) form gels in the same manner at the dilutions 14.8 ± 0.4; 8.4 ± 0.2, 9.4 ± 0.35 and 29.1 ± 0.2, respectively. The time necessary for dissolution of 50 g L?1 pectin gel in intestinal fluid was found to be 70 ± 0.2 min. Pectin gel formed in situ was able to protect Act c 1 from pepsin digestion for 1 h and from further intestinal digestion for one additional hour. CONCLUSION: Pectin gel in an acidic environment protects Act c 1 from pepsin digestion and dissolves slowly in the slightly basic environment of the intestine allowing the survival of fruit allergen for additional time and possible interaction with the gut immune system. Copyright © 2008 Society of Chemical Industry 相似文献
55.
Dragana Stanic Jelena Radosavljevic Natalija Polovic Milka Jadranin Milica Popovic Olga Vuckovic Lidija Burazer Ratko Jankov Tanja Cirkovic Velickovic 《International Dairy Journal》2009,19(12):746-752
The use of enzymes may improve the functional properties of various food ingredients. The aim of this study was to examine the effects of proteolytic contaminants in phenol oxidases on β-lactoglobulin (BLG). In the presence of Trametes versicolor laccase and Agaricus bisporus tyrosinase, both variants of BLG (A and B) underwent removal of a peptide from the N-terminus. The truncated forms were more susceptible to digestion by pepsin. The truncation of BLG resulted from contaminating proteases and not due to the action of phenol oxidases. The removal of N-terminal peptides proceeded quickly, while the rest of the globular protein remained resistant to proteolysis for up to 3 h. In the case of the application of enzymes in food bioprocessing, it may be important to carefully monitor the effects of contaminating proteases in enzyme preparations used. 相似文献
56.
Tanja Brockmann Patrick Fontana Birgit Meng Urs Müller 《Beton- und Stahlbetonbau》2008,103(7):446-454
Nanotechnology in Construction Engineering In general, nanotechnology comprises the development, production and application of materials yielding novel functionalities and performances. In the construction industry and materials research nanotechnology can be utilized for a variety of areas of application, such as the optimisation of material properties, the prevention of damages and the implementation of new functionalities. This article gives an overview of areas in the construction sector where nanotechnology gains prominently of significance, such as cementitious binders, façades, windows and glazing, fire protection, interior decoration and infrastructure buildings. Furthermore, actual scientific research activities in the field of building materials on a nano‐scale performed by the Federal Institute for Materials Research and Testing (BAM) in Berlin are being presented. The research activities relate to the modification of hydrate phases in ultra high performance concrete (UHPC) and to the enhancement of performance of anti‐graffiti‐systems. 相似文献
57.
Linear thermal bridges in vacuum insulated constructions. Continuously rising demands on the structural thermal insulation of heated buildings lead under certain conditions to high efficient insulation materials, which achieve its efficiency by using the vacuum technology. Inside these elements there is a medium vacuum that has to be durable to guarantee the excellent heat insulating characteristic. For that purpose a non‐permeable enveloping of the core material is essential, which breeds around the element edges increased heat losses, especially referring to the element joints concerning large vacuum insulated areas. This paper quantifies these additional heat losses for different constructions based on measurements. 相似文献
58.
Side‐Directed Transfer and Presystemic Metabolism of Selenoneine in a Human Intestinal Barrier Model
Isabelle Rohn Nina Kroepfl Julia Bornhorst Doris Kuehnelt Tanja Schwerdtle 《Molecular nutrition & food research》2019,63(12)
Scope : Selenoneine, a recently discovered selenium (Se) species mainly present in marine fish, is the Se analogue of ergothioneine, a sulfur‐containing purported antioxidant. Although similar properties have been proposed for selenoneine, data on its relevance to human health are yet scarce. Here, the transfer and presystemic metabolism of selenoneine in an in vitro model of the human intestinal barrier are investigated. Methods and results : Selenoneine and the reference species Se‐methylselenocysteine (MeSeCys) and selenite are applied to the Caco‐2 intestinal barrier model. Selenoneine is transferred in higher amounts, but with similar kinetics as selenite, while MeSeCys shows the highest permeability. In contrast to the reference species, transfer of selenoneine is directed toward the blood side. Cellular Se contents demonstrate that selenoneine is efficiently taken up by Caco‐2 cells. Moreover, HPLC/MS‐based Se speciation studies reveal a partial metabolism to Se‐methylselenoneine, a metabolite previously detected in human blood and urine. Conclusions : Selenoneine is likely to pass the intestinal barrier via transcellular, carrier‐mediated transport, is highly bioavailable to Caco‐2 cells and undergoes metabolic transformations. Therefore, further studies are needed to elucidate its possible health effects and to characterize the metabolism of selenoneine in humans. 相似文献
59.
Acid Extraction from Liquid Phase Pyrolysis Oil Using Cyanex®923 and Subsequent Solvent Regeneration
Daniela Painer Klara Treusch Nikolaus Schwaiger Tanja Weiß Peter Pucher Matthus Siebenhofer 《化学,工程师,技术》2019,91(11):1582-1588
Liquid phase pyrolysis (LPP) oil, an intermediate from biofuel production using second‐generation biomass, is a promising source of biobased platform chemicals like acetic acid, however, displaying a complex, multicomponent mixture. Reactive extraction with Cyanex®923 was investigated for selective recovery of acids and subsequent solvent regeneration in distillation at 200 mbar. In a three‐stage extraction 81 % of acids were removed from the LPP oil without loss of Cyanex®923 to the raffinate. Solvent regeneration efficiency of acids was up to 99.7 % with mainly acids and water in the distillate. 相似文献
60.
Oxylipins are bioactive lipids formed by the monooxygenation of polyunsaturated fatty acids (PUFA). Eicosanoids derived from arachidonic acid (ARA) are the most well-studied class of oxylipins that influence brain functions in normal health and in disease. However, comprehensive profiling of brain oxylipins from other PUFA with differing functions, and the examination of the effects of dietary PUFA and sex differences in oxylipins are warranted. Therefore, female and male Sprague–Dawley rats were provided standard rodent diets that provided additional levels of the individual n-3 PUFA α-linolenic acid (ALA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), or the n-6 PUFA linoleic acid (LNA) alone or with ALA (LNA + ALA) compared to essential fatty acid-sufficient control diets. Oxylipins and PUFA were quantified in whole brains using HPLC-MS/MS and GC, respectively. Eighty-seven oxylipins were present at quantifiable levels: 51% and 17% of these were derived from ARA and DHA, respectively. At the mass level, ARA and DHA oxylipins comprised 81–90% and 6–12% of total oxylipins, while phospholipid ARA and DHA represented 25–35% and 49–62% of PUFA mass, respectively. Increasing dietary n-3 PUFA resulted in higher levels of oxylipins derived from their precursor PUFA; otherwise, the brain oxylipin profile was largely resistant to modulation by diet. Approximately 25% of oxylipins were higher in males, and this was largely unaffected by diet, further revealing a tight regulation of brain oxylipin levels. These fundamental data on brain oxylipin composition, diet effects, and sex differences will help guide future studies examining the functions of oxylipins in the brain. 相似文献