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排序方式: 共有624条查询结果,搜索用时 468 毫秒
21.
Rosa Taurino Elena Fabbri Doris Pospiech Alla Synytska Massimo Messori 《Progress in Organic Coatings》2014
Organic–inorganic hybrid coatings on glass substrates with superhydrophobic properties and with improved scratch resistance were obtained by means of applying a multilayer approach including multiple sol–gel processes. The coatings exhibited a water contact angle (WCA) higher than 150°. Ultraviolet (UV)-curable vinyl ester resins and vinyltriethoxysilane (VTEOS) as coupling agent were employed to increase the adhesion between substrate and the inorganic layers. The surfaces were characterized by means of dynamic contact angle and roughness measurements. Indeed, the occurrence of superhydrophobic behavior was observed. The scratch resistance of the hybrid coatings was tested to evaluate the adhesion of the coatings to the glass substrate. The proposed preparation method for scratch resistant, mechanically stable, superhydrophobic coatings is simple and can be applied on large areas of different kinds of substrates. 相似文献
22.
Maria Mytiliniou Joeri A. J. Wondergem Thomas Schmidt Doris Heinrich 《Journal of the Royal Society Interface》2022,19(187)
Intracellular transport is pivotal for cell growth and survival. Malfunctions in this process have been associated with devastating neurodegenerative diseases, highlighting the need for a deeper understanding of the mechanisms involved. Here, we use an experimental methodology that leads neurites of differentiated PC12 cells into either one of two configurations: a one-dimensional configuration, where the neurites align along lines, or a two-dimensional configuration, where the neurites adopt a random orientation and shape on a flat substrate. We subsequently monitored the motion of functional organelles, the lysosomes, inside the neurites. Implementing a time-resolved analysis of the mean-squared displacement, we quantitatively characterized distinct motion modes of the lysosomes. Our results indicate that neurite alignment gives rise to faster diffusive and super-diffusive lysosomal motion than the situation in which the neurites are randomly oriented. After inducing lysosome swelling through an osmotic challenge by sucrose, we confirmed the predicted slowdown in diffusive mobility. Surprisingly, we found that the swelling-induced mobility change affected each of the (sub-/super-)diffusive motion modes differently and depended on the alignment configuration of the neurites. Our findings imply that intracellular transport is significantly and robustly dependent on cell morphology, which might in part be controlled by the extracellular matrix. 相似文献
23.
Delphine Vincent AnhDuyen Bui Doris Ram Vilnis Ezernieks Frank Bedon Joe Panozzo Pankaj Maharjan Simone Rochfort Hans Daetwyler Matthew Hayden 《International journal of molecular sciences》2022,23(2)
Bread wheat is the most widely cultivated crop worldwide, used in the production of food products and a feed source for animals. Selection tools that can be applied early in the breeding cycle are needed to accelerate genetic gain for increased wheat production while maintaining or improving grain quality if demand from human population growth is to be fulfilled. Proteomics screening assays of wheat flour can assist breeders to select the best performing breeding lines and discard the worst lines. In this study, we optimised a robust LC–MS shotgun quantitative proteomics method to screen thousands of wheat genotypes. Using 6 cultivars and 4 replicates, we tested 3 resuspension ratios (50, 25, and 17 µL/mg), 2 extraction buffers (with urea or guanidine-hydrochloride), 3 sets of proteases (chymotrypsin, Glu-C, and trypsin/Lys-C), and multiple LC settings. Protein identifications by LC–MS/MS were used to select the best parameters. A total 8738 wheat proteins were identified. The best method was validated on an independent set of 96 cultivars and peptides quantities were normalised using sample weights, an internal standard, and quality controls. Data mining tools found particularly useful to explore the flour proteome are presented (UniProt Retrieve/ID mapping tool, KEGG, AgriGO, REVIGO, and Pathway Tools). 相似文献
24.
Mende S Krzyzanowski L Weber J Jaros D Rohm H 《Journal of Bioscience and Bioengineering》2012,113(2):185-191
Some Lactobacillus delbrueckii ssp. bulgaricus strains are able to synthesize exopolysaccharides (EPS) and are therefore highly important for the dairy industry as starter cultures. The aim of this study was to investigate the nutritional requirements for growth and EPS production of Lactobacillus delbrueckii ssp. bulgaricus DSM 20081. A medium was developed from a semi-defined medium (SDM) in which glucose was replaced by lactose and different combinations of supplements (nucleobases, vitamins, salts, sodium formate and orotic acid) were added. Constant pH batch fermentation with the modified medium resulted in an EPS yield of approximately 210 mg glucose equivalents per liter medium. This was a 10-fold increase over flask cultivation of this strain in SDM. Although not affecting cell growth, the mixture of salts enhanced the EPS synthesis. Whereas EPS production was approximately 12 mg/g dry biomass without salt supplementation, a significantly higher yield (approximately 20 mg/g dry biomass) was observed after adding the salt mixture. In continuous fermentation, a maximal EPS concentration was obtained at a dilution rate of 0.31/h (80 mg EPS/L), which corresponded to a specific EPS production of 49 mg/g dry biomass. 相似文献
25.
26.
Researchers investigated the impact of podcasting on student motivation in the online environment during fall 2008 and spring 2009. Data were collected from students enrolled in fourteen online courses at a research university in the United States. One hundred and ninety-one students completed a modified version of the Instructional Materials Motivation Survey (Keller, 2006); it has four subscales: attention, relevance, confidence, and satisfaction. Strong positive relationships between all subscales were detected. Results indicate students were moderately motivated by the use of podcasts in their online courses. Statistically significant differences in student motivation based on gender, class standing, and prior online learning experience were found. Benefits of using podcasts and recommendations for improvement of the multimedia files were offered by users. 相似文献
27.
IT/Business Alignment
IT/Business Alignment has become a key issue for many companies. Therefore a lot of companies, institutions and universities
have published documents about this topic. This paper is intended to give an overview of these resources found in the Internet.
相似文献
28.
Helen Shipton Doris Fay Michael West Malcolm Patterson Kamal Birdi 《Creativity & Innovation Management》2005,14(2):118-128
There is growing evidence available to suggest that Human Resource Management (HRM) practice is an important predictor of organizational performance. Drawing upon organizational learning perspectives, we argue that HRM systems also have the potential to promote organizational innovation. We present longitudinal data from thirty‐five UK manufacturing organizations to suggest that effective HRM systems – incorporating sophisticated approaches to recruitment and selection, induction, appraisal and training – predict organizational innovation in products and production technology. We further show that organizational innovation is enhanced where there is a supportive learning climate, and inhibited (for innovation in production processes) where there is a link between appraisal and remuneration. 相似文献
29.
K. A. Jones R. T. Lareau T. Monahan J. R. Flemish R. L. Pfeffer R. E. Sherriff C. W. Litton R. L. Jones C. E. Stutz D. C. Look 《Journal of Electronic Materials》1995,24(11):1641-1648
Symmetric δ-doped InGaP and AlGaAs PHEMT structures have been grown by organometallic vapor phase epitaxy with properties
that approach those of MBE grown AlGaAs structures. The 300 and 77K carrier concentrations for the InGaP PHEMT were 2.72 and
2.56 × 1012 cm2
−2 and the mobilities were 5,920 and 22,000 cm2
2/V.s. These excellent values suggest that problems associated with switching the anion at the channel heterojunction have
been overcome. The corresponding values for the AlGaAs PHEMT were 2.51 and 2.19 × 1012 cm2
−2 and 6,500 and 20,400 cm2/V.s. The uniformity in the indium concentration in the InGaAs layer as determined by photoluminescence, photoreflection,
double crystal x-ray diffraction, and Rutherford backscattering was found to be good, but the percent In in the AlGaAs pseudo-morphic
high electron mobility transistor (PHEMT) was less than that in the InGaP PHEMT even though the programmed values were the
same. The uniformity in the doping distribution as determined by secondary ion mass spectroscopy and electrochemical capacitance-voltage
measurements was found to be good, but it decreased with distance from the center of the susceptor. Also, most of the dopants
in the δ-doped InGaP and AlGaAs layers were activated. 相似文献
30.
This research studies factor analysis of traditional survey- questionnaires for interactive software evaluation in order to construct a Principal Factor Conversion Function (PFCF). Such a PFCF may be used in several ways: first, for exploratory purposes, to discover the principal factors of the traditional questionnaire; second to test the potential of data reduction within significant loss of information; and third to compare the traditional manual evaluation to a condensed computerized interactive software evaluation. A CAI system was used as the software to be evaluated in this research. 相似文献