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101.
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Elizabeth A. Mack 《Papers in Regional Science》2014,93(1):3-29
This study evaluates the relationship between the spatial distribution of broadband providers and the presence of knowledge intensive firm clusters in US counties. Results highlight this relationship is heterogeneous and localized. In some places, broadband appears to be an essential link that enables knowledge firms to strategically locate in lower cost counties and in close proximity to major knowledge centres. In other places, the availability of broadband Internet connections are unable the negative externalities associated with locations in more remote areas of the country. From a policy perspective, this suggests that broadband should be viewed as a key component, but not the only component, of comprehensive local economic development plans. 相似文献
103.
Elizabeth Edwards 《History of Photography》2013,37(2):206-207
Abstract This interesting volume explores the photographic environment and output of four Anglo women who had extended photographic relationships with Native American people: Kate Cory, an artist and collector who lived with the Hopi people for many years; Mary Shaffer; who travelled amongst the Stoney and Metis of Alberta, Canada; Jane Gay, who assisted ethnographer Alice Fletcher and documented land allotment and the effects of the Dawes Act on the Nez Percé people; Grace Nicholson, who set up commercial enterprises trading in art and cultural objects. None of the women was primarily a photographer. Their photographic work was always an adjunct to other purposes, to record encounters commercial, artistic or ethnographic, but at the same time the work functioned as a key articulation of their relationships with Native peoples. All four women, in their different ways, looked to Native American peoples as a way of defining and experiencing their own identities and spirituality and all four shared a commitment to and engagement with these peoples. 相似文献
104.
Elizabeth Manning Luís F. Ramos Francisco M. Fernandes 《Journal of Nondestructive Evaluation》2016,35(3):43
This paper presents the continued development of a novel non-destructive testing method termed tube-jack testing. The goal of the tube-jack system is to provide an enhanced and less destructive method than traditional flat-jack testing for determination of mechanical characteristics and local stress states in irregular masonry walls. Single tube-jack tests were performed, using previously developed rubber tube-jacks, in regular masonry walls of granite and cement-lime mortar. A traditional flat-jack test was also performed in the same masonry wall. Conclusions suggest that tube-jacks are successful in applying pressure to the masonry at low stress states. 相似文献
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De La Torre Jessica Elizabeth Fatma Gassara Anne Patricia Kouassi Khaled Belkacemi 《Critical reviews in food science and nutrition》2017,57(6):1078-1088
Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use. 相似文献
109.
Elsabé Jones Elizabeth Ojewole Rahul Kalhapure 《Drug development and industrial pharmacy》2014,40(5):669-679
Drug delivery via the buccal route has emerged as a promising alternative to oral drug delivery. Didanosine (DDI) undergoes rapid degradation in the gastrointestinal tract, has a short half-life and low oral bioavailability, making DDI a suitable candidate for buccal delivery. Recent developments in buccal drug delivery show an increased interest toward nano-enabled delivery systems. The advantages of buccal drug delivery can be combined with that of nanoparticulate delivery systems to provide a superior delivery system. The aim of this study was to design and evaluate the preparation of novel nano-enabled films for buccal delivery of DDI. Solid lipid nanoparticles (SLNs) were prepared via hot homogenization followed by ultrasonication and were characterized before being incorporated into nano-enabled monolayered multipolymeric films (MMFs). Glyceryl tripalmitate with Poloxamer 188 was identified as most suitable for the preparation of DDI-loaded SLNs. SLNs with desired particle size (PS) (201?nm), polydispersity index (PDI) (0.168) and zeta potential (?18.8?mV) were incorporated into MMFs and characterized. Conventional and nano-enabled MMFs were prepared via solvent casting/evaporation using Eudragit RS100 and hydroxypropyl methylcellulose. Drug release from the nano-enabled films was found to be faster (56% versus 20% in first hour). Conventional MMFs exhibited higher mucoadhesion and mechanical strength than nano-enabled MMFs. SLNs did not adversely affect the steady state flux (71.63?±?13.54?µg/cm2?h versus 74.39?±?15.95?µg/cm2?h) thereby confirming the potential transbuccal delivery of DDI using nano-enabled MMFs. Nano-enabled buccal films for delivery of DDI can be successfully prepared, and these physico-mechanical studies serve as a platform for future formulation optimization work in this emerging field. 相似文献
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