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In an effort to reduce food safety risks, virulent phages are investigated as antibacterial agents for the control of foodborne pathogens. The aim of this study was to evaluate microencapsulation (ME) as a tool to concentrate and store staphylococcal bacteriophages. As a proof of concept, phage Team1 belonging to the Myoviridae family was microencapsulated in alginate gel particles of 0.5 mm (micro-beads) and 2 mm (macro-beads) of diameter. Gel contraction occurred during the hardening period in the CaCl 2 solution, and the diameters of the initial alginate droplets shrunk by 16% (micro-beads) and 44% (micro-beads). As compared to the phage counts in the alginate solution, this contraction resulted in the increase of the phage titers, per g of alginate gel, by factors of 2 (micro-beads) and 6 (micro-beads). The encapsulation yield was highest in the macro-beads. Although phage Team1 was successfully frozen in beads, ME did not improve phage stability to freeze-drying. The addition of glycerol protected the microencapsulated phages during freezing but had no effect on free phage suspensions. Finally, ME improved storage stability at 4 °C but had no impact on freezing or drying over three months of storage.

BACKGROUND: Although the reasons behind tobacco smoking at young age are complex, research has identified curiosity as a potent driver of smoking among adolescents. OBJECTIVE: The objective of the current study is to develop and provide initial evidence of reliability and validity of a short scale assessing smoking curiosity among adolescents (first measure of its kind). In particular, we developed and tested the adolescent smoking curiosity scale (ASCOS). METHODS: After scale development, 101 adolescents completed a survey on smoking-related measures, including ASCOS (June to August, 2014). We conducted exploratory factor analysis and Cronbach’s alpha calculation to inspect factor-structure and reliability. We conducted multiple linear regression models to examine the scale’s capacity to predict antecedents of smoking initiation. RESULTS: Factor analysis supported a single-factor structure of smoking curiosity. ASCOS was internally reliable (Cronbach’s alpha = 0.83). Controlling for demographics, the measure correlated significantly with temptation to try smoking (β=0.41, p

Background Adolescent peers’ influence on tobacco smoking is a dynamic process affected by close friends and other network peers. Although research has examined the influence of immediate friends on smoking behavior (i.e., by cohesion exposure), the influence of all peers according to closeness (i.e., proximity exposure) remains unknown. This study introduces proximity exposure as a potential driver of peer influence. Methods Using the Teenage Friends and Lifestyle Study dataset, we examined 160 adolescents followed for 3 years and assessed their friendship ties and health behavior. Proximity exposure was calculated as the proportion of an individual’s network peers who smoked, considering their distance from the individual. Path analysis was conducted with cross-lagged models testing the effect of proximity exposure on smoking frequency over time. Results Among nonsmokers without cohesion exposure (n = 80), proximity exposure at year 1 was significantly associated with smoking initiation by year 3. Path analysis (n = 160) indicated that smoking at year 1 predicted cohesion exposure by year 3. When proximity exposure was included, the effect of smoking on cohesion exposure was lost. Early smoking predicted future proximity exposure. However, the predictive value of early proximity toward future smoking was stronger. Conclusion These results suggest that proximity exposure can predict smoking even among nonsmokers without direct ties to friends who smoke. In support of a peer selection hypothesis, early smoking predicted friendship formation with smokers through cohesion. Conversely, in support of a peer influence hypothesis, proximity exposure predicted smoking. Researchers may consider developing interventions that decrease proximity exposure among adolescents.

Staphylococcus aureus is one of the most prevalent pathogenic bacteria contaminating dairy products. In an effort to reduce food safety risks, virulent phages are investigated as antibacterial agents to control foodborne pathogens. The aim of this study was to compare sets of virulent phages, design phage cocktails, and use them in a cocktail to control pathogenic staphylococci in cheese. Six selected phages belonging to the three Caudovirales families (Myoviridae, Siphoviridae, Podoviridae) were strictly lytic, had a broad host range, and did not carry genes coding for virulence traits in their genomes. However, they were sensitive to pasteurization. At MOI levels of 15, 45, and 150, two anti-S. aureus phage cocktails, each containing three phages, one from each of the three phage families, eradicated a 10(6)CFU/g S. aureus population after 14 days of Cheddar cheese curd ripening at 4°C. The use of these phages did not trigger over-production of S. aureus enterotoxin C. The use of phage cocktails and their rotation may prevent the emergence of phage resistant bacterial strains.

Highlights • Text messaging is a potentially powerful tool for informing the public about risks. • After 16 texts, the perceived risk of using e-cigarettes was significantly increased. • Tobacco risk communication via texts could help guide healthful choices., Introduction Young adults are rapidly adopting electronic cigarette (e-cigarette) use. The popularity of e-cigarettes among young people can be attributed to heavy industry advertising and misleading health claims. Data indicate that young e-cigarette users who have never used conventional cigarettes may transition toward smoking combustible cigarettes. Communicating e-cigarette risks via text messaging is limited. This pilot study assessed the impact of exposure to 16 text messages on e-cigarette knowledge and risk perception. The short text messages delivered to participants conveyed e-cigarette use may lead to addiction to nicotine and explained the latest health-related findings. Methods A two-group randomized pretest and posttest study was conducted among 95 racially, ethnically diverse young adults recruited from vocational training programs. Fifty percent of participants were randomized to receive either gain- or loss-framed messages. Knowledge and risk perceptions about e-cigarettes and tobacco use were assessed pre- and post-message exposure. Results Participants had a mean age of 20.8 years, SD = 1.7. Current use of e-cigarettes was reported by 10.5% (10/95) and 27.4% (26/95) used a variety of other tobacco products. Findings revealed significant increases in knowledge about e-cigarettes after exposure to the messages (range for ps: p

The existence of a large scale structure of turbulence in a free hot jet is emphasized by measurements carried out on the initial assumption of a fine scale structure. Second order analysis allows one to split the signals picked up in the jet and in the acoustic field into coherent and non-coherent components. The validity of this decomposition with regard to the physical picture of the phenomenon, i.e. vortices convected in the mixing zone, is tested by means of conditional sampling analysis, applied for several diagnostics.