Monitoring bicycle trips is no longer limited to traditional sources, such as travel surveys and counts. Strava, a popular fitness tracker, continuously collects human movement trajectories, and its commercial data service, Strava Metro, has enriched bicycle research opportunities over the last five years. Accrued knowledge from colleagues who have already utilised Strava Metro data can be valuable for those seeking expanded monitoring options. To convey such knowledge, this paper synthesises a data overview, extensive literature review on how the data have been applied to deal with drivers’ bicycle-related issues, and implications for future work. The review results indicate that Strava Metro data have the potential—although finite—to be used to identify various travel patterns, estimate travel demand, analyse route choice, control for exposure in crash models, and assess air pollution exposure. However, several challenges, such as the under-representativeness of the general population, bias towards and away from certain groups, and lack of demographic and trip details at the individual level, prevent researchers from depending entirely on the new data source. Cross-use with other sources and validation of reliability with official data could enhance the potentiality.
1 March 2020 in Transportation Research Interdisciplinary Perspectives
As bicycling on roadways can cause adverse health effects, there is an urgent need to understand how bicycle routes expose bicyclists to traffic emissions. Limited resources for monitoring reveal that bicycle travel patterns may constrain such understanding at the network level. This study examined the potential exposure of bicyclists to traffic-related air pollution in El Paso, Texas, using Strava Metro data that revealed bicycle patterns across the city networks. An initial spatial mapping analysis was conducted to explore the spatial patterns of bicycling and traffic pollutant emission, followed by exploratory descriptive statistics. A spatial bicycle model was then developed to explore factors influencing bicycling activity in El Paso. Analysis results indicated significant associations between greater bicycle volume and both higher levels of particulate matter (PM2.5) emissions and more frequent bus services, implying adverse health concerns related to traffic-related air pollution. The results also indicated significant effects of various environmental characteristics (e.g., roadway, bicycle infrastructure, topography, and demographics) on bicycling. The findings encourage extending this study to provide guidance to bicyclists whose regular trips take place on heavily trafficked roads and during rush hours in this region and to evaluate the net health impacts of on-road bicycling for the general population.
Hepatocellular carcinoma (HCC) constitutes more than 90% of all primary liver cancers. HCC is a hypervascular tumor that develops from dedifferentiation of small avascular HCC and is therefore a good target for anti-angiogenic gene therapy. Recent studies have identified apolipoprotein(a) [apo(a)] kringles LK68 and LK8 (LKs) as having a potential anti-angiogenic and anti-tumor activity, and the current study evaluates the therapeutic potential of gene therapy with recombinant adeno-associated virus carrying genes encoding LKs (rAAV-LK) in the treatment of hypervascular HCC. We generated rAAV-LK to obtain persistent transgene expression
in vivo
, which is essential for anti-angiogenic therapy. The rAAV-produced LKs substantially inhibited proliferation and migration of human umbilical vein endothelial cells (HUVECs)
in vitro
, validating their anti-angiogenic potential. Intramuscular administration of rAAV-LK gave 60% to 84% suppression (
P
< .05) of tumor growth in mice bearing subcutaneously transplanted HCC derived from Huh-7 and Hep3B cells, respectively. Histological and immunohistochemical analyses of HCC tumor sections showed that a single administration of rAAV-LK gave rise to persistent expression of LKs that inhibited tumor angiogenesis and triggered tumor apoptosis, and, thus, significantly suppressed tumor growth. The administration of rAAV-LK provided a significant survival benefit (
P
< .05), and 3 of 10 rAAV-LK–treated mice were still alive without visible tumors and without clinical symptoms 188 days after treatment.
In conclusion,
rAAV-LK is a potential candidate for anti-angiogenic gene therapy in the treatment of HCC. (Hepatology 2006;43:1063–1073.)
12 September 2019 in International Journal of Sustainable Transportation
Using data from the Houston Travel-Related Activity in Neighborhoods (TRAIN) study, this study examined how various factors affect whether individuals intend to use newly opened light-rail transit (LRT) lines in Houston. The Houston TRAIN study is a natural experiment on the effect of new LRT lines on both transit use and physical activity. A mixed binary logit model was developed based on a dichotomous dependent variable and rich set of variables, including sociodemographic factors, health status, travel behavior and technology, and attitudes and perceptions. The mixed model also allowed accounting for the unobserved heterogeneity across individuals in their sensitivity to observed variables. The results indicated the important role of various factors influencing the decision on intent to use the new LRT lines. In general, demographics mattered but to a lower extent than psychological or personality-related variables. For example, attitudes and perceptions toward the public transit system and consciousness of physical activities derived by using public transit were important factors. Personal health constraints negatively influenced intention to use, while experience with the public transport system was among the positive indicators. The findings show the potential of future interventions in this community to promote use of the new system, such as educational campaigns that improve perceptions of public transit use and clarify the benefits of being active. While providing growing evidence that cognitive variables are important in measuring intention to use public transit, the results emphasize the positive role of efforts integrating transportation and health to develop effective and sustainable solutions.