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141.
An antibacterial peptide (AMP), i.e., nisin, was covalently bound to gelatin through a protein–protein coupling. Various reaction conditions were tested to study and optimize parameters of grafting e.g., orientation and density of AMP, which could impact the final antibacterial activity of the modified biopolymer. Modification was investigated by Fourier transform infrared (FT‐IR) spectroscopy and zeta potential. The antibacterial activity of the nisin‐enriched gelatin was evaluated against two staphylococci bacterial strains, i.e., Staphylococus epidermidis and Staphylococcus aureus. A higher activity was found for gelatin modified at pH = 7.4 revealing an influence of the nisin orientation on the protein antibacterial property. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41825. 相似文献
142.
143.
K Papadakis FI Luks ME De Paepe GJ Piasecki CW Wesselhoeft 《Canadian Metallurgical Quarterly》1997,32(2):347-351
We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE. Thus, the age-dependent and coordinate diminution in cell proliferative activity and cell death events may serve to maintain the thickness of the OE as mice mature and age. 相似文献
144.
Richard Akinyeye Mantoa Sekota Priscilla Baker Emmanuel Iwuoha 《Fullerenes, Nanotubes and Carbon Nanostructures》2006,14(1):49-55
A preliminary result of the morphology and yield of chemically synthesized polypyrrole (PPY) using β-naphthalene sulfonic acid (NSA) and ammonium peroxodisulphate (APS) in aqueous medium is presented. Various micro/nanotubes were obtained using different dopant/monomer (D/M) ratios and temperature settings. Similar but shorter and sheet-like nanostructures were obtained without the use of surfactant NSA; with a fibre-like, loose and admixed physical outlook. The percentage yield (m/v) of the doped PPY was greater than that from the undoped, being 27-44 and 18-20, respectively with higher values obtained from the low temperature synthesis. The highest percentage yield of 44 was obtained from a D/M ratio of 0.8. 相似文献
145.
Owing to the corrosive conditions in coastal areas, aluminium alloy railings and similar structures are normally used on infrastructure works such as bridges and roads located in such areas because aluminium alloys are inherently corrosion resistant. However, to achieve rigid support, aluminium alloy members are often embedded in concrete. Consequently, the embedded parts undergo corrosion caused by the alkaline content of the cement used in the concrete. This research was carried out to study the corrosion behaviour on both the embedded and unembedded sides of aluminium alloy A6061-T6 members embedded in the concrete and also to investigate the ability of a combined coating of anodic oxide and organic film to inhibit corrosion. Additionally, the influence of scratch damage on the performance of this coating material was evaluated. 相似文献
146.
Minas M. Stylianakis George D. Spyropoulos Emmanuel Stratakis Emmanuel Kymakis 《Carbon》2012,50(15):5554-5561
3,5-Dinitrobenzoyl chloride was covalently linked to graphene oxide (GO) nanosheets prepared by a modified Hummers’ method, using ethylenediamine as a spacer. The linkage of the GO with the small molecule was confirmed by spectroscopic (e.g., Fourier transform infrared, Raman) and microscopic analyses. The resultant GO-ethylene-dinitro-benzoyl (GO-EDNB) consists of a controlled scale of different graphene structures and is highly dispersable in common organic solvents. The GO-EDNB was used as the electron acceptor material in poly-(3-hexylthiophene) (P3HT) bulk heterojunction photovoltaic devices to significantly improve the performance, yielding a power conversion efficiency improvement of two orders and one order of magnitude compared with the pristine P3HT and the P3HT-GO devices respectively. 相似文献
147.
Van Zundert Rinka M. P.; Engels Rutger C. M. E.; Kuntsche Emmanuel 《Canadian Metallurgical Quarterly》2011,25(2):301
Recent research has shown that daily changes in self-efficacy predict lapses and relapse into smoking after quitting among adolescent daily smokers, but it is not known if and how momentary self-efficacy is associated with affect-motivational states and external contexts. In the present study, 134 adolescent daily smokers were monitored daily during 1 week prior to and 3 weeks after they began their quit attempt. Participants completed questions on smoking, self-efficacy, affect-motivational states (craving and negative affect), and external contexts (seeing others smoke, experiencing a stressful event, and alcohol and coffee consumption) three times a day. Affect-motivational states as well as all external contexts (except for coffee consumption) were associated with lower self-efficacy when participants were still abstinent, but also after they had lapsed. Associations between the situational contexts and self-efficacy did not largely depend on individual characteristics such as baseline self-efficacy and age. Among girls, however, the negative associations between self-efficacy and negative affect and drinking alcohol were found to be stronger. These results show that adolescents' self-efficacy during a quit attempt may be responsive to affect-motivational states and external contexts, both before and after lapsing. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
148.
149.
Emmanuel Kalogeris Paul Christakopoulos Dimitris Kekos Basil J. Macris 《Journal of Bioscience and Bioengineering》1999,87(6):819
The mode of action of a minor xylanase on a variety of polysaccharides and model substrates was investigated. The enzyme was excreted by Thermoascus aurantiacus grown in solid state fermentation (SSF). The purified enzyme had a molecular mass of 33,000. Thin layer chromatography analysis showed that the endoxylanase liberated short fragments from polysaccharides. The enzyme hydrolysed aryl-β-
-cellobioside and the chromogenic (fluorogenic) 4-methylumbelliferyl-β-glycosides of xylobiose (MeUmbXyl2) and xylotriose (MeUmbXyl3) at the agluconic linkage. The results suggested that the endoxylanase belonged to family 10. 相似文献
150.
Petros Androvitsaneas Andreas F. Terzis Emmanuel Paspalakis 《Quantum Information Processing》2013,12(2):831-840
We investigate entanglement formation in antiferromagnetic and mixed anisotropic, finite, one-dimensional Heisenberg chains with and without the presence of a uniform magnetic field. We explore the thermal entanglement created in terms of the bounds of the localizable entanglement and the possibility for quantum phase transitions in the zero field cases by means of standard quantum Monte Carlo method. 相似文献