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This paper aims to assess the adsorption behaviour and the adhesion strength of lubricant films formed by polypropylene oxide-polyethylene oxide-polypropylene oxide (PPO-PEO-PPO) with phosphate ester additive on Ti-coated surface and to identify the influence of molecular architecture and phosphate ester additive.

The thickness of the adsorbed PPO-PEO-PPO with phosphate ester lubricant films on Ti surfaces was measured by ellipsometry. The adhesion strength of the copolymer and the copolymer with phosphate ester lubricants was studied by the micro-scratch tests; the scratch tracks on the surfaces were observed by atomic force microscopy and scanning electronic microscopy.

The copolymer with a higher weight percentage of PPO not only formed a thicker film but also showed stronger adhesion and better lubrication performance. The added phosphate ester increased the film thickness and improved the tribological behaviour. The finding reveals that the adsorbed film thickness which depends on the PPO chain length and the presence of phosphate ester has a considerable effect on the scratch behaviour.

This paper fulfils the studies about adsorption behaviour and lubrication mechanism of this new lubricant which has not been adequately investigated on the metal surface.

Narrative comments about dentists on physician review sites have been documented to increasingly influence people's selection of their dentists. From a communication standpoint, these comments are a type of narrative communication that people share their experiences with dentists by telling stories. Based on the frameworks of rhetoric structure theory and extended elaborated likelihood model, this study aimed to examine the effects of such storytelling from two perspectives including narrative structure and narrative focus.

A 4 (narrative structure) × 2 (narrative focus) between-subjects experiment was conducted to examine the proposed hypotheses and research questions

The results showed that a one-sided comprehensive comment focusing on technical competence generated the strongest persuasion effects measured by attitude and behavioral intention. These effects were mediated by perceived narrative credibility and enjoyment.

This study contributes to the extant literature in two ways. First, it extends previous studies of online narrative comments by showing which narrative structure and focus are deemed to be more persuasive when selecting a dentist. Second, it offers a test of two routes of information processing (i.e. cognitive and experiential) to understand the mechanism underlying the effects of narrative comments.

The peer-review history for this article is available at: https://publons.com/publon/10.1108/OIR-08-2020-0359

The Monascus pigment has been widely applied in the food processing industry as a functional additive. Lovastatin and polysaccharides are two important bio-active materials found in Monascus. Citrinin is considered as mycotoxin. Thus, it is important to produce high yields of intracellular Monascus pigments with high yields of lovastatin and polysaccharides, while maintaining low citrinin yields under liquid fermentation.

The intracellular yields of pigments, lovastatin, polysaccharides and citrinin; biomass; and reducing the sugar content of Monascus purpureus HBSD 08 were determined every day during a 10-day culturing period using lactose, maltose, sucrose, glucose, glycerine and xylose as the sole carbon sources. Additionally, the pigment composition was analysed by a thin layer chromatography (TLC) and the in vitro antitumor activities of the pigments were determined.

The maximal yield of pigments (55.44 U/mL after six days of culture) and lovastatin content (1,475.30 µg/L after five days of culture) were obtained in the presence of glucose and maltose as the sole carbon sources, respectively. The suitable carbon sources for high intracellular polysaccharides yields were sucrose, maltose and xylose. Glucose should not be chosen as the sole carbon source because of its high food safety risk. In vitro antitumor activities of pigments in the presence of different carbon sources were in the order of xylose > glucose = maltose > glycerine > sucrose = lactose. The pigment compositions in the presence of different carbon sources were the same from the TLC analysis. Thus, maltose displayed high intracellular yields of pigments, lovastatin and polysaccharides; high food safety against citrinin, and high in vitro antitumor activity during the ten days culturing period.

This study shows us the benefits of using maltose as a substrate in the production of intracellular Monascus pigments while ensuring economic and food safety.