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排序方式: 共有874条查询结果,搜索用时 15 毫秒
71.
72.
Cecilia Elofsson Petr Dejmek Marie Paulsson Hans Burling 《International Dairy Journal》1997,7(12):2988
β-Lactoglobulin, standard whey protein concentrate (WPC 80) and cold-gelling whey protein concentrate (mWPC 80) were dried onto mica sheets at 0.03-3 μg cm−2 surface load and imaged with atomic force microscopy (AFM) in tapping mode. β-Lactoglobulin and WPC 80 spread to a fairly even 2.5 nm thick layer at about monolayer surface load, while mWPC showed particle sizes of 20-30 nm laterally. There is little difference in the observed structures between 0.3 and 3 μg cm−2 apart from the higher surface load. At 0.03 μg cm−2, β-lactoglobulin spread somewhat more thinly than WPC 80. With the addition of DTT, mWPC spread evenly with only few particles in evidence. AFM appears to be a convenient method for the characterization of aggregation states of sub-micrometer protein particles. 相似文献
73.
Fredrik Johansson Martin Kanje Cecilia Eriksson Linsmeier Lars Wallman 《IEEE transactions on bio-medical engineering》2008,55(4):1447-1449
xonal outgrowth on smooth and porous silicon surfaces was studied in organ culture. The pore size of the silicon substrata varied between 100 and 1500 nm. We found that axons preferred to grow and elongate on porous silicon surfaces only when pores of (150-500 nm) are available. 相似文献
74.
Fernanda de Carvalho Panzeri Pires‐de‐Souza Renata Espíndola Silveira Gabriel Abuna Michelle Alexandra Chinelatti Carla Cecilia Alandia‐Román Mario Alexandre Coelho Sinhoreti 《Microscopy research and technique》2015,78(12):1062-1068
The purpose of this study was to analyze, by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM), the morphology of sealant/enamel interface after surface treatment with Biosilicate. Before pits and fissures sealing, the occlusal surfaces of 10 sound human molars were sectioned perpendicularly at the fissures in order to obtain three slices for each tooth. Slices were randomly assigned into three groups (n = 10) according to sealing protocol: Group 1‐ Acid etching + Biosilicate + glass ionomer‐based sealant (Clinpro XT Varnish, 3M ESPE); Group 2‐ Acid etching + glass ionomer‐based sealant (Clinpro XT Varnish, 3M ESPE); Group 3‐ No sealing. All slices were subjected to thermal cycling (5,000 cycles; 5–55°C; dwell time: 30s). Half of the slices from each group (n = 5) were analyzed by CLSM and the other half by SEM. Groups 1 and 2 were also submitted to EDS analysis and their data were evaluated by Two‐Way ANOVA e Tukey's test (α=5%). EDS data analysis showed higher amounts of silicon (Si) ions than calcium (Ca) ions in Group 1 (P < 0.05); Group 2 presented higher amounts (P < 0.05) of Ca ions than Si ions. It may be concluded that the use of Biosilicate for surface treatment did not affect the morphology of glass ionomer‐based sealant/enamel interfaces. Microsc. Res. Tech. 78:1062–1068, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
75.
Total carotenoid content and composition of carotenoids of six varieties of Bactris gasipaes were determined by spectrophotometry and HPLC, with photodiode array detector. Significant differences in total carotenoid content (1.1 to 22.3 mg/100g) were detected among these varieties. Boiling the fruits for 30 minutes did not affect total carotenoid content, but did change the amount of some specific carotenoids, mainly by the production of Z-isomers. Peach palm varieties had the same carotenoids, but in different proportions, presenting mainly, all E-beta-carotene (26.2% to 47.9%), Z-gamma-carotene (18.2% to 34.3%) and Z-lycopene (10.2% to 26.8%). When antioxidant activity was evaluated using DPPH, it was observed that the variety with higher percentages of beta-carotene (54.1%) presented the higher activity. This is one of the first reports in carotenoid content and antioxidant activity in well typified varieties of Bactris gasipaes, whose results could have a positive impact in the consumption of certain peach palm varieties. 相似文献
76.
Díaz MD Palomino-Schätzlein M Corzana F Andreu C Carbajo RJ del Olmo M Canales-Mayordomo A Pineda-Lucena A Asensio G Jiménez-Barbero J 《Chembiochem : a European journal of chemical biology》2010,11(17):2424-2432
The conformations of two synthetic pentapeptides with antimicrobial activity and their 4-fluorophenylalanine (Pff)-containing analogues (ArXArXAr-NH(2); Ar=Phe, Pff; X=Lys, Arg) have been studied. NMR experiments carried out both in aqueous fluoroalcohol solutions and SDS micelles permitted their interactions with membrane-like environments to be explored. WaterLOGSY experiments and Mn(2+)-based paramagnetic probes were also applied to assess their orientations with respect to the SDS micelles. In addition, pulse-field gradient (PFG) diffusion NMR spectroscopy studies were conducted, under different experimental conditions (i.e., concentration, temperature) to characterize the possible changes in the peptides' aggregation states as a putative critical factor for their antimicrobial activity. Finally, molecular dynamics simulations on a variety of conformations showed the intrinsic flexibility of these peptides in both aqueous solutions and membrane-mimetic systems. 相似文献
77.
Determining consumer purchase intentions: the importance of dry matter, size, and price of kiwifruit
Jaeger SR Harker R Triggs CM Gunson A Campbell RL Jackman R Requejo-Jackman C 《Journal of food science》2011,76(3):S177-S184
Abstract: Knowledge of the relative importance of food quality attributes in determining consumer purchase intention is critical for robust assessment of economic opportunities for industry growth. The aim of this study is to demonstrate how conjoint analysis methodology that incorporates tasting of fruit can be used to collect such information. Three hundred Japanese consumers took part in research designed to measure the importance of dry matter (DM), size, and price of kiwifruit (Actinidia deliciosa “Hayward” and Actinidia chinensis “Hort16A”) for purchase intention. Measurement of consumer liking for kiwifruit of different DM content was a key first step. Liking increased as DM increased and was accompanied by increased purchase likelihood/choice probability for kiwifruit. The size of kiwifruit presented to consumers varied from “small” to “extra large.” Consumers liked “mid‐sized” kiwifruit over “small” or “extra‐large” kiwifruit. Despite these differences in liking, size was of little importance in determining purchase likelihood/choice probability for kiwifruit. Price was a very important factor in determining purchase likelihood/choice probability but was less important than DM content. As price increased, purchase likelihood/choice probability decreased. Beneath these general findings, heterogeneity existed. Some consumers placed more/less importance on the focal purchase drivers than suggested by the aggregate model. Overall, the results suggest that incentive schemes already implemented by industry should consider rewarding high‐DM fruit more than fruit size. Practical Application: This research has contributed to the New Zealand kiwifruit industry gaining a better understanding of the relative importance consumers place on DM, size, and price of kiwifruit and has resulted in changes to grower incentive schemes. The research approach presented forces consumer to tradeoff attributes of kiwifruit against each other and decide on how important two key quality attributes—DM and size—are relative to each other and relative to price. The application of conjoint analysis in this article can be transferred to other fruits, food, and beverages and help guide consumer‐led innovation. 相似文献
78.
Industrial product development requires continuous improvements in work procedures as a result of constantly changing demands.
Support tools have proven to be an oft chosen way to meet new demands; however, few research efforts have been made in how to implement new tools. This article is a contribution to knowledge on carrying out the implementation of support tools. The basis consists
of four field studies performed during 1994–1999, containing 78 qualitative research interviews and focusing on the implementation
and use of different support tools. A re-analysis has been performed of selected interviews from the field studies, in total
30 interviews. This resulted in recommendations for an implementation framework, consisting of an Implementation Cycle, Organizational Change Field and Managerial Consistence, and five implementation keys: Goal setting, Kowledge Development, Anchoring at All Levels, Suitable Resources and Focus on the Individual. 相似文献
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