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91.
Benedetta Pasquini Mohammad Goodarzi Serena Orlandini Giangiacomo Beretta Sandra Furlanetto Bieke Dejaegher 《International Journal of Food Science & Technology》2014,49(5):1351-1359
In this article, discrimination models are presented, relating the origin of honey samples to several variables, being the concentrations of different cations and anions in the honey samples measured by ion chromatography, and parameters that measure/reflect the antioxidant activity of the honey samples. The unsupervised method, principal component analysis, and supervised discrimination methods, such as linear and quadratic discriminant analysis, and classification and regression trees (CART), were applied to evaluate the existence of data patterns and the relationship between geographical origin and the measured parameters. The model with the best predictive ability (%CCRTEST = 66.67%), the best overall % specificity (80%) and the best overall % sensitivity (67%) was found to be CART. It was proven that the mineral content and parameters analysed can provide enough information for the geographical characterisation and discrimination of honey. 相似文献
92.
A Systematic Structure–Activity Study of a New Type of Small Peptidic Transfection Vector Reveals the Importance of a Special Oxo-Anion-Binding Motif for Gene Delivery
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Dr. Sandra Junghänel Sarah Karczewski Sandra Bäcker Prof. Dr. Shirley K. Knauer Prof. Dr. Carsten Schmuck 《Chembiochem : a European journal of chemical biology》2017,18(22):2268-2279
We discovered a new class of artificial peptidic transfection vectors based on an artificial anion-binding motif, the guanidiniocarbonylpyrrole (GCP) cation. This new type of vector is surprisingly smaller than traditional systems, and our previous work suggested that the GCP group was important for promoting critical endosomal escape. We now present here a systematic comparison of similar DNA ligands featuring our GCP oxo-anion-binding motif with DNA ligands only consisting of naturally occurring amino acids. Structure–activity studies showed that the artificial binding motif clearly outperformed natural amino acids such as histidine, lysine, and arginine. It improved the ability to shuttle foreign genetic material into cells, yet successfully mediated endosomal escape. Also, plasmids that were complexed by our artificial ligands were stabilized against cytosolic degradation to some extent. This resulted in the successful expression of plasmid information (comparable to gold standards such as polyethyleneimine). Hence, our study clearly demonstrates the importance of the tailor-made GCP anion-binding site for efficient gene transfection. 相似文献
93.
Florian Röper Markus Wolfahrt Sandra Schlögl Georg Kucher Gerald Pinter 《应用聚合物科学杂志》2019,136(19):47506
Repair of composite structures and the impact of demanding environmental conditions is a crucial issue for the aircraft industry because of the increasing use of composites in modern aircraft. Consequently, the impact of environmental conditions common for aircraft applications on repair specimens in comparison to nonrepaired specimens is studied. All specimens are produced from a woven carbon fiber-reinforced epoxy-based prepreg. For the repair-specimens, an epoxy-based film adhesive is used for the soft patch repair approach. During the repair process, the surface of the precured prepreg is prepared by a mechanical method (sanding) and an additional chemical functionalization, respectively. Moisture absorption of the repair specimens is independent of the surface preparation method and higher for the repaired than for the nonrepaired specimens. The key influencing environmental conditions for the tensile strength and the failure mode of the repair specimens are elevated temperature testing as well as hot/wet conditioning and conditioning in deionized water. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47506. 相似文献
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Altered blood flow during embryonic development has been shown to cause cardiac defects; however, the mechanisms by which the resulting haemodynamic forces trigger heart malformation are unclear. This study used heart outflow tract banding to alter normal haemodynamics in a chick embryo model at HH18 and characterized the immediate blood flow response versus the degree of band tightness. Optical coherence tomography was used to acquire two-dimensional longitudinal structure and Doppler velocity images from control (n = 16) and banded (n = 25, 6–64% measured band tightness) embryos, from which structural and velocity data were extracted to estimate haemodynamic measures. Peak blood flow velocity and wall shear rate (WSR) initially increased linearly with band tightness (p < 0.01), but then velocity plateaued between 40% and 50% band tightness and started to decrease with constriction greater than 50%, whereas WSR continued to increase up to 60% constriction before it began decreasing with increased band tightness. Time of flow decreased with constriction greater than 20% (p < 0.01), while stroke volume in banded embryos remained comparable to control levels over the entire range of constriction (p > 0.1). The haemodynamic dependence on the degree of banding reveals immediate adaptations of the early embryonic cardiovascular system and could help elucidate a range of cardiac adaptations to gradually increased load. 相似文献
96.
Sandra P.O Dwyer David OBeirne Deirdre Ní Eidhin Brendan T. OKennedy 《Journal of food science》2012,77(12):N58-N65
Abstract: This study examined the effectiveness of fat and water soluble antioxidants on the oxidative stability of omega (ω)‐3 rich table spreads, produced using novel multiple emulsion technology. Table spreads were produced by dispersing an oil‐in‐water (O/W) emulsion (500 g/kg 85 camelina/15 fish oil blend) in a hardstock/rapeseed oil blend, using sodium caseinate and polyglycerol polyricinoleate as emulsifiers. The O/W and oil‐in‐water‐in‐oil (O/W/O) emulsions contained either a water soluble antioxidant (green tea extract [GTE]), an oil soluble antioxidant (α‐Tocopherol), or both. Spreads containing α‐Tocopherol had the highest lipid hydroperoxide values, whereas spreads containing GTE had the lowest (P < 0.05), during storage at 5 °C, while p‐Anisidine values did not differ significantly. Particle size was generally unaffected by antioxidant type (P < 0.05). Double emulsion (O/W/O) structures were clearly seen in confocal images of the spreads. By the end of storage, none of the spreads had significantly different G′ values. Firmness (Newtons) of all spreads generally increased during storage (P < 0.05). Practical Application: Lipid oxidation is a major problem in omega‐3 rich oils, and can cause off‐odors and off‐flavors. Double emulsion technology was used to produce omega‐3 enriched spreads (O/W/O emulsions), wherein the omega‐3 oil was incorporated into the inner oil phase, to protect it from lipid oxidation. Antioxidants were added to further protect the spreads by reducing lipid oxidation. Spreads produced had good oxidative stability and possessed functional (omega‐3 addition) properties. 相似文献
97.
Explaining the Formation of Online News Startups in France and the United States: A Field Analysis
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This article examines the differential formation of online news startups in Toulouse, France, and Seattle, United States. While Seattle is home to many startups, in Toulouse there have been just 4—and only 1 continues publishing. Drawing on Bourdieu's field theory, we argue that amount and types of capital held by journalists in the 2 cities varied as a result of differences in journalism's position in the field of power. These differences shaped the extent of startup formation in each city and structured journalists' capacities to convert their capital into the resources needed to form startups (e.g., funding, credentials, partnerships). These findings are positioned in relation to literatures on journalism innovation and comparative media. 相似文献
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99.
María V. Fernández Rosa J. Jagus Sandra L. Mugliaroli 《Food and Bioprocess Technology》2014,7(9):2528-2537
The effect of nisin alone and in combination with Microgard? on the natural microbial flora of ricotta cheese and in post-process contamination with Listeria innocua was studied. Microbial groups studied were mesophilic, psychrotrophic, proteolytic, lactic acid and coliform bacteria, and total molds and yeasts. Considering the evolution of all microbial groups and failure criteria adopted for mesophilic and coliform bacteria, this product reached the end of its shelf life before 5 days, which is insufficient time for product commercialization. The combined use of nisin and Microgard? proved to be more effective than the individual application on these microbial groups, resulting in a 13 days shelf life extension. Additionally, the combined treatment reduced the growth of L. innocua as a post-process contamination. 相似文献
100.