Policies and interventions involving the built environment have become a promising opportunity for the promotion of walking as a sustainable transportation mode. Among voluminous literature, few studies were found that examined the association between the built environment and walking among the elderly in China. This study investigated the relationship between the built environment and the walking activity of the elderly based on data collected in Zhongshan Metropolitan Area, China. The results suggest that abundant sidewalks, dense bus stops, easily accessible commercial establishments, and ample green land space are potentially effective to enhance walking among the elderly, albeit to varied degrees. The compact urban form, which is considered as walkability in the western context, may not necessarily play a positive role in Zhongshan's context. The findings provide insights into the policy-making to promote sustainable transportation modes and the design of interventions on health promotion of the elderly in China.

Rational design of covalent organic frameworks (COFs) to broaden their diversity is highly desirable but challenging due to the limited, expensive, and complex building blocks, especially compared with other easily available porous materials. In this work, we fabricated two novel bioinspired COFs, namely, NUS-71 and NUS-72, using reticular chemistry with ellagic acid and triboronic acid-based building blocks. Both COFs with AB stacking mode exhibit high acetylene (C2H2) adsorption capacity and excellent separation performance for C2H2/CO2 mixtures, which is significant but rarely explored using COFs. The impressive affinities for C2H2 appear to be related to the sandwich structure formed by C2H2 and the host framework via multiple host–guest interactions. This work not only represents a new avenue for the construction of low-cost COFs but also expands the variety of the COF family using natural biochemicals as building blocks for broad application.

No abstract

Planners and policy makers have recognized the effects of the built environment on vehicle ownership and use. Within the voluminous literature, however, few studies have examined how the built environment was associated with household electric bike (e-bike) ownership. This study explored the relationship between the built environment and household e-bike ownership in the Chinese context, on the basis of data collected in the Zhongshan Metropolitan Area. The e-bike choice models suggested that household measures dominated the number of household e-bikes, but the models also detected a relationship between several built environment attributes and household e-bike ownership. All else being equal, denser and higher mixed land use development, more connective transportation links, and accessibility to commerce and jobs were related to lower household e-bike ownership. Households located in urban neighborhoods tended to own fewer e-bikes than those in suburban or rural areas. The availability of competitive transportation modes was strongly related to the likelihood of e-bike ownership. The results suggested that policy makers should consider built environment attributes with respect to policies on e-bike ownership and set different policies in different areas according to the variations in the built environments. The findings also suggested that e-bike ownership policies should be integrated with ownership policies on competitive modes and with policies related to public transportation service improvement.