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Nitrogen availability might play an essential role in plant diseases by enhancing fungal cell growth and influencing the expression of genes required for successful pathogenesis. Nitrogen availability could modulate secondary metabolic pathways as evidenced by the significant differential expression of several core genes involved in mycotoxin biosynthesis and genes encoding polyketide synthase/nonribosomal peptide synthetases, cytochrome P450 and carbohydrate-active enzymes in Fusarium sacchari, grown on different nitrogen sources. A combined analysis was carried out on the transcript and metabolite profiles of regulatory metabolic processes and the virulence of Fusarium sacchari grown on various nitrogen sources. The nitrogen regulation of the gibberellin gene cluster included the metabolic flux and multiple steps of gibberellin synthesis. UHPLC-MS/MS-based metabolome analysis revealed the coordination of these related transcripts and the accumulation of gibberellin metabolites. This integrated analysis allowed us to uncover additional information for a more comprehensive understanding of biological events relevant to fungal secondary metabolic regulation in response to nitrogen availability.

Demand-responsive technologies are rapidly changing the transportation landscape. The City of Belleville, Ontario has recently replaced its evening and nighttime fixed route bus service with an on-demand transit (ODT) service. Preliminary reports have found a 300% increase in nighttime bus ridership since the implementation of this service, yet to fully understand the social return on the investment in on-demand services, we must also quantify whether and for whom these new services have enabled time savings and increased levels of activity participation. Furthermore, it remains unclear whether riders are satisfied with the service, and whether satisfaction levels have an impact on activity participation. As such, this study explores the determinants of activity participation of ODT users using a custom ridership survey instrument. We collect information on travel experience, satisfaction, and perceived changes in activity participation due to ODT. We then performed a factor analysis and estimated structural equation models to identify the relationships between aspects of the ODT service and activity participation. Our results show that reliability and service quality are the most important aspects of the ODT services in terms of positively influencing activity participation, and that shorter wait times, are most likely to lead to an increase in activity participation. Our findings further suggest that Belleville can eliminate barriers to nighttime activity participation by providing reliable and affordable ODT service, and that ODT can be an effective solution to provide transit services for transport-poor in low demand areas or during low demand periods of the day. Supplementary Information The online version contains supplementary material available at 10.1007/s11116-021-10215-2.

Millions of North Americans stopped riding public transit in response to COVID-19. We treat this crisis as a natural experiment to illustrate the importance of public transit in riders’ abilities to access essential destinations. We measured the impacts of riders forgoing transit through a survey of transportation barriers completed by more than 4,000 transit riders in Toronto and Vancouver (Canada). We used Heckman selection models to predict six dimensions of transport disadvantage and transport-related social exclusions captured in our survey. We then complemented model results with an analysis of survey comments describing barriers that individuals faced. Lack of access to alternative modes is the strongest predictor of a former rider experiencing transport disadvantage, particularly neighborhood walkability and vehicle ownership. Groups at risk of transport disadvantage before COVID-19, particularly women and people in poorer health, were also more likely to report difficulties while avoiding public transit. Barriers described by respondents included former supports no longer offering rides, gendered household car use dynamics, and lack of culturally specific or specialized amenities within walking distance. Policymakers should plan for a level of redundancy in transportation systems that enables residents to access essential destinations when unexpected service losses occur. Designing communities that enable residents to walk to those essential destinations will help reduce the burdens faced by transit riders during crises that render transit unfeasible. At the same time, planners championing active travel as an alternative to transit during such crises also need to devise solutions for former transit riders for whom active travel is ill suited, for example, due to physical challenges with carrying groceries or needing to chaperone children.