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• An approach combining wildland fire science and transportation engineering is used to assess community directional vulnerabilities for wildfire evacuation. • We look at communities in Alberta, Canada that were assessed as being potentially vulnerable to wildfire. • We explore the directional configuration of roadways in relation to a directional assessment of wildfire exposure. • Some communities, often remote, have egress routes highly exposed to potential wildfire encroachment. • Some larger communities need attention, given relationships between estimated fire travel times and evacuation times. Wildfires are a natural part of forest ecosystems, but sometimes pose a threat to communities. In Canada, when public safety is threatened by a wildfire encroaching into the wildland-urban interface (WUI), fire management agencies will recommend that local authorities evacuate the area. If a fire spreads quickly towards a community and egress capacity is insufficient, public safety can be compromised. This paper presents an interdisciplinary approach for assessing community directional vulnerabilities for wildfire evacuation, combining techniques from wildland fire science and transportation engineering. For a selection of communities in Alberta that were assessed as being potentially vulnerable to wildfire, we explored the directional configuration of the transportation network in relation to a directional assessment of wildfire exposure. We first plotted the viable fire pathways and transportation facility characteristics, and then compared estimated fire encroachment times against estimated community egress times, directionally around each community to show evacuation vulnerabilities. Our results show that some communities, mainly within the Boreal Forest, Foothills and Rocky Mountain natural regions, have egress routes that are highly exposed to potential wildfire encroachment. Our findings also indicate that the evacuation timing for some larger communities needs attention, given relationships between estimated fire travel times and evacuation times. The results can be used to inform evacuation preparedness planning and proactive mitigation efforts. [ABSTRACT FROM AUTHOR]

Air travelers originating from the catchment areas of airports – typically defined by administrative or geographic boundaries – will sometimes "leak" across these boundaries to farther, often larger airports that offer more attractive services and options. To investigate the attractiveness of different airports based on their proximity and geographic position relative to one another, we assess the airport choices of air passengers across a large region of the US Midwest that spans multiple administrative boundaries and airports. We combine a dataset of air tickets purchased by these passengers with other publicly available datasets, and apply mixed logit airport choice models based on air service attributes and airport access distance. We take multiple subsets of the total air tickets dataset using Halton sampling in order to achieve model estimation convergence. Model estimates are compared between data subsets, and consistently lead to the following key results. First, changes in air service attributes on short- and medium-length routes will have a more uniform influence on air passengers' airport choices, compared with long routes. Second, comparable proportional changes in air service attributes lead to greater changes in the catchment areas and market shares of small and medium airports, compared with large hubs. Within these service characteristics, airfare is found to impact passengers' airport preferences more than flight frequency. Finally, the catchment areas and market shares of small- and medium-size airports are influenced by the proximity and geographic location of neighboring airports; this differs from the catchments of large airports, which strongly extend into multiple jurisdictional boundaries in all directions despite the presence of surrounding airports. The study results provide further insight into the influence of air service attributes on long-distance airport choices over large geographic regions served by a diverse set of airports, and the resulting implications on multimodal transportation planning within and across such regions. [ABSTRACT FROM AUTHOR]

Given their distinct service and demand characteristics, flight operations at different airports and the resulting emissions are not expected to be uniformly impacted by price-based environmental policies such as carbon offset charges, carbon taxes and carbon credits. In order to understand the variabilities, we explore the relationship among airfare (a proxy for price-based policies), passenger demand, airline capacity decisions, and resulting aviation emissions on several air routes originating from a small and a large airport in the US Midwest. Using a supply-and-demand model, emissions are found to be inelastic to airfare overall, although they appear to respond to airfare tenfold more at the small airport compared to the large one. This inelasticity suggests that price-based measures will have low efficacy towards directly reducing aviation emissions, despite their role in generating financial resources for supporting various carbon removal and reduction technologies and processes. Given that the studied airports are only about a 2-h drive apart, the aforementioned emissions' response variability show that studying and designing price-based policy instruments at national, continental and global scales, as done extensively thus far, may mask significant regional variations. Replicating this more localized approach on airports in different regions of the US as well as other countries may yield a range of insights about where price-based environmental policies could have efficacy and to what extent. [ABSTRACT FROM AUTHOR]

• The Four Types of Cyclists typology generates heterogeneous comfort patterns. • Our data-driven segmentation yields more homogeneous comfort patterns. • Cyclists form three categories, not four, based on comfort, intent, frequency. • Types: Uncomfortable or Uninterested, Cautious Majority, Very Comfortable Cyclists. The Four Types of Cyclists is a widely adopted typology developed by Portland's Bicycle Coordinator, Roger Geller. No Way No How, Interested but Concerned, Enthused and Confident, and Strong and Fearless have become ubiquitous in academic literature and practice. However, the classification was subjectively developed and contains several known contradictions. This research aims to develop a data-driven typology using near-identical explanatory variables to those of the Four Types of Cyclists. The objective is to develop a typology with a similar functional purpose, but derived using statistical methods. An online survey was distributed to a panel of Edmonton, Canada, residents to this effect, and the use of video clips rather than descriptions is tested as a means to assess comfort on different types of cycling infrastructure. Cluster Correspondence Analysis is used to carry out the segmentations, including variables of comfort, cycling intent, and cycling in the previous summer. The survey sample tends to segment into three categories, as opposed to the four suggested by Geller: Uncomfortable or Uninterested, Cautious Majority, and Very Comfortable Cyclists. The Four Types of Cyclists typology is also shown to generate heterogeneous comfort patterns within each cyclist type, a limitation our empirically-derived segmentations overcome. [ABSTRACT FROM AUTHOR]

Historically an important transportation corridor in the Northwest Territories, climate change has shortened the duration of the Mackenzie River's navigational season. Communities rely increasingly on airlift as the growing volatility affects barging operations, leading to higher overall freight costs. Using an options approach, we present a methodological framework that supports flexible infrastructure decision making, accounting for the impacts of climate change uncertainty. We apply this method to the decision of whether to continue barging on the Mackenzie River, or connect the entire corridor by extending the all-weather Mackenzie Valley Highway, explicitly considering uncertainties in river barging conditions. We first model river open season days as a stochastic process; barging is dependent on the number of open season days, which in turn is affected by climate change. Second, we evaluate the expected cost of barging and airlift each season using a modified Black-Scholes model. Finally, we use real options to determine how long construction of the all-weather highway may be deferred. The results indicate that it is advisable to defer construction nearly a decade, in balancing the costs of construction against climate change uncertainty. This paper demonstrates that when we explicitly incorporate the impact of climate change on project valuations, particularly those in northern and Arctic Canada where these impacts are considerable, project valuations can change significantly such that all-weather road construction is supported, even if it is deferred to future years. This method can assist federal and territorial governments in communicating the impacts of climate change on communities, and provide another tool to support multi-layered, complex transportation infrastructure investment decisions that address these rapidly changing environments. [ABSTRACT FROM AUTHOR]

Between 2000 and 2010, newly merged U.S. airlines decreased service to airports in small and mid-sized metropolitan regions, opting to consolidate their operations at high-value airport hubs (passenger transfer points). At this point travelers living in small and mid-sized regions likely began leaking, or abandoning their local airport to take flights from hub airports offering more convenient flight options. The extent of this practice, however, is not well established. Our study asks to what extent airline consolidation deepened the divide in service levels between airports that are 100–300 miles apart, and seeks to estimate the magnitude of air traveler leakage at small and medium airports across the U.S. We estimate that travelers living in small and mid-sized metropolitan regions have the incentive to “leak” from their airport to a distant, better-served airport. Our estimates suggest that 15.7%–31.8% of the total passengers living proximate to a small or mid-sized airport have the incentive to leak. Our estimates range from 10.8% to 33.0% for travelers facing a non-stop itinerary from their local airport and 33.3%–85.1% for travelers facing a connecting itinerary. The potential leaked passengers contribute 1–2.75% of average daily highway traffic at heavily congested portions of the interstate highways connecting airports and up to 10–12% of traffic on low density portions of the highway. Our study illustrates the relationship between interregional surface transportation and the aviation system by estimating the number of travelers who may choose to travel long distances by car to access a relatively busier, larger airport with better service. The results of this study help to shape the evolving role of airport managers in controlling demand and delay at major hub airports and in building and managing air service and smaller airports across the U.S. [ABSTRACT FROM AUTHOR]

The Mackenzie River is a major transportation route serving many remote northern Canadian communities and mining sites. The river is only navigable during the summer and early fall, when clear of ice. However, the river’s water conditions have changed significantly in recent years, and are expected to continue to do so, resulting in increased uncertainty for waterway transport. This paper presents a model for providing guidance to shipping companies, customers, and government on how shipping patterns may need to evolve to effectively adapt to changing climate conditions. Future freight volumes are forecasted using time series analysis. Then, logistics cost optimization is used to incorporate predicted water flow profile changes in shipping companies’ future delivery schedule planning. Results indicate that future waterway freight delivery capacities in September and October may be insufficient to transport forecasted volumes, and shipping companies may be advised to arrange for increased delivery activities in June and July. If delivery capacities are constrained by equipment and crew availability rather than water conditions in the first half of the shipping season, shipping companies may also need to take advantage of earlier anticipated ice breakup to begin the delivery season earlier. Incorporating this method for climate change adaptation in freight schedule planning may aid both shipping companies and government agencies in rethinking current practices. The method is particularly suitable for a region where harsh environmental conditions, climate change, and extreme remoteness have an overwhelming impact on operations, and logistical delays are considered quite differently from supply chains further south. [ABSTRACT FROM AUTHOR]

In this study, we explore how short- and no-notice evacuation instructions may be designed by a risk-averse emergency management body, explicitly considering varying levels of evacuee compliance and responses to these instructions in the design. The population compliance rate, or its distribution, are unlikely to be known; even a small error in estimating either could lead to drastically worse outcomes. Our solution, which is based on the idea of hedging, determines optimal evacuation instructions in a range of possible scenarios. As part of the proposed solution algorithm, we utilize conditional-value-at-risk (CVaR) and stochastic optimization paradigms to demonstrate how and when compliance uncertainty is a critical input for improved evacuation instructions. Our findings show that in situations where compliance rates are low or highly uncertain, relying solely on highly risk-averse strategies is unlikely to deliver efficient outcomes in comparison to a naïve or no-information approach (where instructions are designed assuming 100% compliance). Although accounting for compliance uncertainty in designing evacuation instructions can be highly beneficial, the added benefits are realized beyond certain population compliance rate levels and uncertainty ranges. This work provides insights into how emergency managers can best overcome non-compliance to instruction, the benefits which are realized together with efforts to promote compliance (community education initiatives and improved communication mechanisms). • Studying the problem of instructing evacuations under varying levels of evacuees' compliance. • Designing a solution based on the idea of hedging against a range of possible scenarios. • Providing insights into how emergency managers can best overcome non-compliance to instruction. [ABSTRACT FROM AUTHOR]

• Consolidated air services at hub airports in the U.S. encourage passenger leakage. • Compared to smaller airports, trips from large hub airports consume less fuel per passenger-kilometer. • Trips from large hubs also result in less pollutants per passenger-kilometer. Attractive air services at large airports in the U.S., over the last two decades, have encouraged interregional air passenger leakage, a phenomenon in which air travelers abandon their nearby small airports in favor of starting their air journeys from large hub airports farther away. The disparities between small and large airports, in terms of air services, are expected to widen because of COVID-19 and further exacerbate passenger leakage. This study estimates the differences in mean aviation fuel consumed and pollutants emitted between air routes from small and large airports in the U.S. Midwest region – routes that are known to be contested according to analysis of an air ticket dataset. Findings indicate that air journeys originating from large airports result in 24% less aviation fuel consumption and considerably lower emissions at the passenger-kilometer level, offering additional insight toward better understanding the environmental impact of a geographically shifting air travel demand. [ABSTRACT FROM AUTHOR]

Abstract: Glutamatergic modulation of inhibitory interneurons plays a crucial role in shaping the flow of information in the cerebral cortex. In a cohort of postmortem human brains from schizophrenia (n =20), bipolar disorder (n =20) and normal control (n =20) subjects, we colocalized the mRNA for the N-methyl-d-aspartate (NMDA) receptor NR2A subunit, labeled with [35S], and the mRNA for the γ-aminobutyric acid (GABA) synthesizing enzyme glutamic acid decarboxylase (GAD)67, labeled with digoxigenin. We found that the density of GAD67+ neurons in layers 2–5 of the prefrontal cortex was decreased by 27–36% in both schizophrenia and bipolar disorder. In addition, the density of the GAD67+/NR2A+ neurons was decreased by 57% and 49% in layers 3 and 4, respectively, in schizophrenia, but it was unchanged in bipolar disorder. These findings raise the possibility that glutamatergic innervation of inhibitory interneurons via the NMDA receptor in the prefrontal cortex may be selectively altered in schizophrenia. [Copyright &y& Elsevier]

Goal-directed behavior is characterized by flexible stimulus-action mappings. The lateral intraparietal area (area LIP) contains a representation of extra-personal space that is used to guide goal-directed behavior. To examine further how area LIP contributes to these flexible stimulus-action mappings, we recorded LIP activity while rhesus monkeys participated in two different cueing tasks. In the first task, the color of a central light indicated the location of a monkey's saccadic endpoint in the absence of any other visual stimuli. In the second task, the color of a central light indicated which of two visual targets was the saccadic goal. In both tasks, LIP activity was modulated by these non-spatial cues. These observations further suggest a role for area LIP in mediating endogenous associations that link stimuli with actions. [ABSTRACT FROM AUTHOR]

• A scheduling model for an urban mobile photo radar speed enforcement program. • Connect traffic safety goals to roadside deployment of limited resources in operator shifts. • Data-driven and systematic enforcement resource allocation in location and time. We present a scheduling model for an urban mobile photo radar speed enforcement (MPE) program. An MPE program utilizes automated photo radar technology to capture speed limit violators, towards an aim to reduce speeding and thus, improve traffic safety. We propose a binary quadratic program that determines where (by location visit tasks) and when (in shifts) to send enforcement resources (operators and equipment) over a month-long schedule. The aim of this program is to minimize violations of enforcement time halos (and thus, efficiency losses) in attaining traffic-safety focused program goals. We solved this problem using a combined Dantzig-Wolfe and column generation optimization approach, after exploring several different types of commonly-used solution methods. The model is applied to a currently operational MPE program in the City of Edmonton, Canada. Using a five-day enforcement time halo, we find that our model results improve resource utilization by 24% over historical program deployment. The scheduling model is the final step of a larger unified MPE program framework that systematically and efficiently connects high-level urban traffic safety goals down shift-level allocations of highly limited enforcement resources. It provides a data-driven and transparent framework that both contributes to cities' pursuits of Vision Zero and combatting negative public perceptions of MPE programs. Additionally, the framework can be easily adapted for, and transferred to, other automated traffic enforcement technologies across jurisdictions. [ABSTRACT FROM AUTHOR]

Human induced pluripotent stem cells (hiPSCs) possess the potential to differentiate toward vascular cells including endothelial cells (ECs), pericytes, and smooth muscle cells. Epigenetic mechanisms including DNA methylation and histone modification play a crucial role in regulating lineage differentiation and specification. Herein, we utilized a three‐stage protocol to induce differentiation of mesoderm, vascular progenitors, and ECs from hiPSCs and investigated the regulatory effects of histone acetylation on the differentiation processes. We found that the expression of several histone deacetylases (HDACs), including HDAC1, HDAC5, and HDAC7, were greatly upregulated at the second stage and downregulated at the third stage. Interestingly, although HDAC1 remained in the nucleus during the EC differentiation, HDAC5 and HDAC7 displayed cytosol/nuclear translocation during the differentiation process. Inhibition of HDACs with sodium butyrate (NaBt) or BML210 could hinder the differentiation of vascular progenitors at the second stage and facilitate EC induction at the third stage. Further investigation revealed that HDAC may modulate the stepwise EC differentiation via regulating the expression of endothelial transcription factors ERG, ETS1, and MEF2C. Opposite to the expression of EC markers, the smooth muscle/pericyte marker ACTA2 was upregulated at the second stage and downregulated at the third stage by NaBt. The stage‐specific regulation of ACTA2 by HDAC inhibition was likely through regulating the expression of TGFβ2 and PDGFB. This study suggests that HDACs play different roles at different stages of EC induction by promoting the commitment of vascular progenitors and impeding the later stage differentiation of ECs. Significance statement: Histone modification play a crucial role in regulating endothelial differentiation. In this study, we found the expression of several HDACs fluctuated significantly during endothelial differentiation. Inhibition of HDACs with sodium butyrate or BML210 could hinder or facilitate EC induction at different differentiation stages. [ABSTRACT FROM AUTHOR]

Several stationary phases based on silica hydride were evaluated as possible separation media for drugs of abuse. In the RP mode both a C18 and a phenyl column were tested using ACN/water and methanol/water mobile phases with formic acid or ammonium formate as modifiers. Detection was performed using MS, so separation of isobaric species was a factor in selecting the column, mobile phase composition, and gradient. A number of sample preparation procedures were also included as part of determining the most appropriate experimental protocol on these types of stationary phases. Morphine was used as a model for developing a protocol that would be suitable for the analysis of hydrophilic drugs. [ABSTRACT FROM AUTHOR]

This paper describes a study undertaken to assess the speed and safety effects of reducing speed limits from 50 to 30 km/h in school zones. Mean speeds and 85th percentile speeds were reduced by 12.2 and 11.6 km/h, respectively. Speed variation was also reduced, and the speed cumulative distributions shifted to the left, indicating further reductions for all speed ranges. The safety evaluation results revealed fatal and injury collisions were significantly reduced by 45.3% and injuries to vulnerable road users were reduced by 55.3%. In fact, for every 1 km/h reduction in mean speed, fatal and injury crashes were reduced by about 4%, which is consistent with findings from previous research. Neither spatial nor temporal collision migration or spillover effects were significant factors in the analysis. Consequently, the results of this study provide strong evidence that reducing speed limits to 30 km/h in school zones can bring significant safety benefits by reducing vehicular speeds and fatal and injury crashes. [ABSTRACT FROM AUTHOR]