Social participation in the city: exploring the moderating effect of walkability on the associations between active mobility, neighborhood perceptions, and social activities in urban adults.

BACKGROUND: Living in urban environments is associated with several health risks (e.g., noise, and air pollution). However, there are also beneficial aspects such as various opportunities for social activities, which might increase levels of social participation and (physically) active mobility that in turn have positive effects on health and well-being. However, how aspects of the environment, active mobility, and social participation are associated is not well established. This study investigates the moderating effect of low vs. high walkability neighborhoods on the associations between active mobility, and social participation and integrates individuals' subjective perception of the neighborhood environment they are living in. METHODS: Cross-sectional data from 219 adults (48% female, mean age = 46 ± 3.8 years) from 12 urban neighborhoods (six low, six high walkability) were analyzed: First, social participation, active mobility, and subjective neighborhood perceptions were compared between people living in a low vs. high walkability neighborhood via t-tests. Second, multigroup path analyses were computed to explore potential differences in the associations between these variables in low vs. high walkability neighborhoods. RESULTS: Social participation, active mobility, and subjective neighborhood perceptions didn't differ in low vs. high walkability neighborhoods (p: 0.37 - 0.71). Active mobility and subjective neighborhood perceptions were significantly stronger related to social participation in low vs. high walkability neighborhoods (active mobility in low: ß = 0.35, p < .01 vs. high: ß = 0.09, p = .36; subjective neighborhood perceptions in low: ß = 0.27, p < .01 vs. high: ß = 0.15, p = .18). CONCLUSIONS: Despite living in neighborhoods with objectively different walkability, participants rated social participation and active mobility equally and perceived their neighborhoods similarly. However, zooming into the interrelations of these variables reveals that social participation of residents from low walkability neighborhoods depends stronger on active mobility and perceiving the environment positively. Positive perceptions of the environment and active mobility might buffer the objectively worse walkability. Future research should focus on underlying mechanisms and determinants of subjective neighborhood perceptions and active mobility, especially in low walkability neighborhoods.

The inherent antibiotic activity of myxobacteria-derived autofluorescent outer membrane vesicles is switched on and off by light stimulation.

Outer membrane vesicles are small, lipid-based vesicles shed from the outer membrane of Gram-negative bacteria. They are becoming increasingly recognised as important factors for resistance gene transfer, bacterial virulence factors and host cell modulation. The presence of pathogenic factors and antimicrobial compounds in bacterial vesicles has been proven in recent years, but it remains unclear, if and how environmental factors, such as light specifically regulate the vesicle composition. We report the first example of autofluorescent vesicles derived from non-pathogenic soil-living myxobacteria. These vesicles additionally showed inherent antibiotic activity, a property that is specifically regulated by light stimulation of the producing bacteria. Our data provide a central basis for better understanding the environmental impact on bacteria-derived vesicles, and design of future therapeutic options.

Analyzing Person-Place Interactions During Walking Episodes: Innovative Ambulatory Assessment Approach of Walking-Triggered e-Diaries.

BACKGROUND: Walking behavior is positively associated with physiological and mental health as much evidence has already shown. Walking is also becoming a critical issue for health promotion in urban environments as it is the most often used form of active mobility and helps to replace carbon dioxide emissions from motorized forms of transport. It therefore contributes to mitigate the negative effects of climate change and heat islands within cities. However, to promote walking among urban dwellers and to utilize its health-enhancing potential, we need to know more about the way in which physical and social environments shape individual experiences during walking episodes. Such person-place interactions could not adequately be analyzed in former studies owing to methodological constraints. OBJECTIVE: This study introduces walking-triggered e-diaries as an innovative ambulatory assessment approach for time-varying associations, and investigates its accuracy with 2 different validation strategies. METHODS: The walking trigger consists of a combination of movement acceleration via an accelerometer and mobile positioning of the cellphone via GPS and transmission towers to track walking activities. The trigger starts an e-diary whenever a movement acceleration exceeds a predetermined threshold and participants' locations are identified as nonstationary outside a predefined place of residence. Every 420 (±300) seconds, repeated e-diaries were prompted as long as the trigger conditions were met. Data were assessed on 10 consecutive days. First, to investigate accuracy, we reconstructed walking routes and calculated a percentage score for all triggered prompts in relation to all walking routes where a prompt could have been triggered. Then, to provide data about its specificity, we used momentary self-reports and objectively assessed movement behavior to describe activity levels before the trigger prompted an e-diary. RESULTS: Data of 67 participants could be analyzed and the walking trigger led to 3283 e-diary prompts, from which 2258 (68.8%) were answered. Regarding accuracy, the walking trigger prompted an e-diary on 732 of 842 (86.9%) reconstructed walking routes. Further, in 838 of 1206 (69.5%) triggered e-diaries, participants self-reported that they were currently walking outdoors. Steps and acceleration movement was higher during these self-reported walking episodes than when participants denied walking outdoors (steps: 106 vs 32; acceleration>0.2 g in 58.4% vs 19% of these situations). CONCLUSIONS: Accuracy analysis revealed that walking-triggered e-diaries are suitable to collect different data of individuals' current experiences in situations in which a person walks outdoors. Combined with environmental data, such an approach increases knowledge about person-place interactions and provides the possibility to gain knowledge about user preferences for health-enhancing urban environments. From a methodological viewpoint, however, specificity analysis showed how changes in trigger conditions (eg, increasing the threshold for movement acceleration) lead to changes in accuracy.

How do people feel while walking in the city? Using walking-triggered e-diaries to investigate the association of social interaction and environmental greenness during everyday life walking.

Background: Light to moderate physical activity, which includes walking, is associated with positive effects on physical and mental health. However, concerning mental health, social and physical environmental factors are likely to play an important role in this association. This study investigates person-place interactions between environmental characteristics (greenness, social interaction) and momentary affective states during walking episodes. A within-subject design is implemented, in which affective states and environmental characteristics are assessed while participants are walking outside. Methods: On smartphones, coupled with a motion sensor (move3), e-diaries were triggered as soon as people walked 100 m outside. E-diaries assessed momentary affective states (valence, calmness, energetic arousal), and social interaction (walking alone; seeing other people while walking; interacting with other people; walking with a known person) between 6 am and 10 pm over nine days. The percentage of greenness was determined afterward from recorded GPS and GIS data. Demographics were collected in advance via an online questionnaire. Multilevel models were calculated with R for 46 individuals (age = 41.2, ± 13.2; 52% female). Results: Affective state dimension energetic arousal showed a significant association with social interaction and greenness, i.e., participants rated energetic arousal lower when walking alone, and if there was less greenness vs. when interacting shortly with someone while walking (ß = 0.13, p = 0.02), and being in situations with more greenness (ß = 0.08, p = 0.02). Furthermore, associations with social interaction and greenness were found for dimension calmness: walking together with someone was associated with higher calmness (ß = 0.16, p = 0.02), and the higher the proportion of surrounding greenness during a walk, the higher calmness was rated, i.e., participants were calmer (ß = 0.09, p = 0.01). Significant associations with valence were not present. Conclusion: The findings indicate that the affective states varied significantly due to different social and physical environmental factors. In the future, the importance of environmental factors should be further investigated, e.g., by assessing environmental factors right in situations contrary to a subsequent imputation. Within-subject designs, and in particular triggered assessments with the addition of GPS, can aid in developing interventions for health-promoting urban environments.

Poloxamer 188 as surfactant in biological formulations - An alternative for polysorbate 20/80?

Surfactants are used to stabilize biologics. Particularly, polysorbates (Tween® 20 and Tween® 80) dominate the group of surfactants in protein and especially antibody drug products. Since decades drug developers rely on the ethoxylated sorbitan fatty acid ester mixtures to stabilize sensitive molecules such as proteins. Reasons are (i) excellent stabilizing properties, and (ii) well recognized safety and tolerability profile of these polysorbates in humans, especially for parenteral applications. However, over the past decade concerns regarding the stability of these two polysorbates were raised. The search of alternatives with preferably less reservations concerning degradation and product quality reducing issues leads, among others, to poloxamer 188 (e.g. Kolliphor® P188), a nonionic triblock-copolymer surfactant. This review sums up our current knowledge related to the characterization and physico-chemical properties of poloxamer 188, its analytics and stability properties for biological formulations. Furthermore, the advantages and disadvantages as a suitable polysorbate-alternative for the stabilization of biologics are discussed.