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61.
62.
Factors influencing the formation and properties of lutein‐loaded nanoemulsions fabricated using spontaneous emulsification (SE) were investigated. Nanoemulsion formation depended on oil type: small droplets (diameter ≈ 200 nm) with a narrow monomodal particle size distribution (polydispersity index ≈ 0.23) could be formed using medium‐chain triglycerides (MCT), but not long‐chain triglycerides. Nanoemulsion formation also depended on surfactant type and concentration, with Tween 80 being the most effective surfactant. Optimisation of lutein‐loaded nanoemulsions formed by SE led to systems with a final composition of 10 wt% oil phase (0.12 wt% lutein + 9.88 wt% MCT), 10 wt% Tween 80, and 80 wt% aqueous phase. The nanoemulsions were stable to droplet aggregation when stored at ambient temperature for up to 1 month; however, some colour fading occurred due to lutein degradation. This study indicated the potential of nanoemulsion‐based delivery system fabricated using a low‐energy method for encapsulation and protection of lutein.  相似文献   
63.
Re-establishing a functional endothelium following endovascular treatment is an important factor in arresting neointimal proliferation. In this study, both histology (in vivo) and computational simulations (in silico) are used to evaluate neointimal growth patterns within coronary arteries along the axial direction of the stent. Comparison of the growth configurations in vivo and in silico was undertaken to identify candidate mechanisms for endothelial repair. Stent, lumen and neointimal areas were measured from histological sections obtained from eight right coronary stented porcine arteries. Two re-endothelialization scenarios (endothelial cell (EC) random seeding and EC growth from proximal and distal ends) were implemented in silico to evaluate their influence on the morphology of the simulated lesions. Subject to the assumptions made in the current simulations, comparison between in vivo and in silico results suggests that endothelial growth does not occur from the proximal and distal ends alone, but is more consistent with the assumption of a random seeding process. This may occur either from the patches of endothelium which survive following stent implantation or from attachment of circulating endothelial progenitor cells.  相似文献   
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Effects of surfactant concentration, antioxidants with different polarities, and chelator type on the oxidative stability of water‐in‐stripped walnut oil (W/O) emulsions stabilized by polyglycerol polyricinoleate (PGPR) were evaluated. The formation of primary oxidation products (lipid hydroperoxides) and secondary oxidation products (hexanal) decreased with increasing PGPR concentrations (0.3–1.0 wt% of emulsions). Excess surfactant might solubilize lipid hydroperoxides out of the oil–water interface, resulting in the decreased lipid oxidation rates in W/O emulsions. At concentrations of 10–1000 μM, the polar Trolox demonstrated concentration‐dependent antioxidant activity according to both hydroperoxide and hexanal formation. The antioxidant efficiency of the non‐polar α‐tocopherol was slightly reduced at the higher range of 500–1000 μM based on hydroperoxide formation. Both ethylenediaminetetraacetic acid (EDTA) and deferoxamine (DFO) at concentrations of 5–100 μM reduced the rates of lipid oxidation at varying degrees, indicating that endogenous transition metals may promote lipid oxidation in W/O emulsions. EDTA was a stronger inhibitor of lipid oxidation than DFO. These results suggest that the oxidative stability of W/O emulsions could be improved by the appropriate choice of surfactant concentration, antioxidants, and chelators.  相似文献   
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67.
Landscape Urbanism has been, to date, a theory emerging primarily from the Western world. This paper counters the Western focus by exploring the potential of Landscape Urbanism theory in Dubai. In a previous article published by the author, landscape architecture in Dubai has been identified as diverging from the tenets of the various charters of the International Federation of Landscape Architects (IFLA), having apparently scant regard for pressing ecological, social and cultural design issues. Landscape Urbanism in this paper is discussed with respect to its ability to bolster the practice of landscape architecture in Dubai in relation to these issues. The paper argues that a number of key facets of Landscape Urbanism appear difficult to reconcile with the ecological, social and cultural conditions of Dubai. Further to this, it tends to lack the tools by which landscape urbanists in Dubai could link theory with practice.  相似文献   
68.
探讨了不同掺量的有机硅BS94对脱硫石膏吸水率、抗折强度、抗压强度、初凝时间、终凝时间的影响规律,分析了脱硫石膏中杂质对有机硅BS94防水性能的影响。结果表明,有机硅BS94对以脱硫石膏为原料生产的耐水纸面石膏板具有较好的防水性能,可以广泛应用于以脱硫石膏生产耐水纸面石膏板的工艺中,但当脱硫石膏中的F离子含量较高时,防水剂的防水性能会有所下降,因此,应严格控制原料中可溶性F的含量。  相似文献   
69.
Vacant land in cities is an important resource as it presents opportunities for urban renewal and revitalisation and can contribute to municipal revenue. In a context of growing informality and homelessness in cities of the South, the presence of large tracts of vacant land is a sign of inefficient urban planning and a dysfunctional land market. It is therefore critical for local governments to have reliable data of the extent of vacant land parcels in cities and their potential for housing development, particularly affordable housing for the poor. This paper will detail and discuss the “Potential Housing Land Model” developed by the Cape Urban Observatory, part of the African Centre for Cities, based at the University of Cape Town, South Africa. South African cities, and in this case the city of Cape Town in particular, face huge constraints in terms of suitable, well-located and affordable land for low-cost housing development. A tool like the “Potential Housing Land Tool” is one tool which could assist decision-makers in identifying such land parcels. Besides identifying land that can potentially be used for housing; the model can also allow officials to pin-point areas that are not well-serviced. The deployment of the model on the World Wide Web makes the tool available to a range of users including municipal officials, academic researchers and organised sectors of civil society who might benefit from this kind of information. The responsible and strategic use of this model and the information it provides, can facilitate a broad-based discussion about vacant land and its potential use in the city, allowing for more transparent and participatory planning. The application of tools like the “Potential Housing Land Tool” can therefore greatly assist in improving urban governance and can contribute towards more efficient and sustainable urban planning and management systems.  相似文献   
70.
Due to its rheological properties, positive lead-acid battery paste can be difficult to spread on lead current collectors accurately and efficiently under industry machinery and setting. Sodium polymethacrylate dispersant was studied as an effective positive paste additive that could lower the yield stress of the paste without affecting paste density and battery performance. Under a four-blade vane rheometer setup, stress growth and oscillatory amplitude strain sweep experiments evaluated the rheological properties of positive paste with the addition of varying amounts of sodium polymethacrylate. Further, the electrochemical effects of sodium polymethacrylate were also evaluated in 2V batteries by testing positive active material utilization and cycle life.  相似文献   
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