Island Of Montreal Research Articles

Integrated Intervening Opportunities Model for Public Transit Trip Generation–Distribution

An integrated intervening opportunities model (IIOM) was developed for public transit (PT) trips. This model is generation–distribution and supply-dependent, with single constraints only on trip production values for work and study PT trips made during morning peak hours (6:00 to 9:00 a.m.) within the Island of Montreal, Quebec, Canada. Several data sets, including the 2008 origin–destination survey of the Greater Montreal Area, 2006 census of Canada, General Transit Feed Specification network data, and school enrollment data, along with the geographical data of the Greater Montreal Area, were used. The IIOM is a nonlinear model with sociodemographic, socioeconomic, and PT supply characteristics, as well as work and study spatial location attributes. Analysis of the modeling performance by means of several goodness-of-fit measures showed that the IIOM was well behaved (i.e., globally it had good prediction capabilities) and more accurate than the classical gravity model. On the basis of explanatory variables used in the IIOM, the study presents a new tool for PT analysts, planners, and policy makers for studying potential changes in PT trip patterns, as a result of changes in sociodemographic and socioeconomic characteristics, PT supply, and so on. Also, this study opens new opportunities for development of more accurate PT demand models with new emergent data such as smartcard entries.

"River Flow, Sewer Flow, Street Flow

River Flow, Sewer Flow, Street Flow is a location-based, interactive mobile soundscape originally presented in Old Montreal at DHC-ART1 as part of the exhibition Lost Rivers: La Petite St. Pierre. The exhibition took up mobility as a curatorial challenge and featured videos and photographs by underground explorer Andrew Emond and sound compositions by Samuel Thulin. The exhibition thematically resurrected the historic water systems that once traversed the island of Montreal. Daylighting is the process of bringing creeks, streams, and rivers that were buried during the industrial period to the surface. Lost Rivers invited participants to daylight the meandering contours of La Petite St. Pierre virtually on a wintery Montreal night.

Do You Have the Time?: Modernity, Democracy, and the Beginnings of Daylight Saving Time in Montreal, 1907–1928

This article looks at the most significant public debate over time in Montreal’s history: the beginnings of daylight saving time (1907–1928). Seeing daylight saving time as an example of the disembedding of time from place, the article demonstrates the importance of local social dynamics in the creation of meanings of modernity. Daylight saving time began as an idea to save money and improve people’s lives, though it was ridiculed until the First World War, when it was put in place in Montreal and much of North America and Europe. Yet after the war, it was rejected as a national measure, and subsequently much of North America and eventually even the Island of Montreal turned into a patchwork of time zones. The article argues that the difficult beginnings of daylight saving time in Montreal were due to the unequal benefits of changing the clock, rural–urban tensions, the Canadian federal system, conflicts between ethno-religious institutions, Montreal’s tenacious mayor, and the economic power of businesses to shape time. Cet article se penche sur l’implantation progressive de l’heure avancée (1907–1928), objet du plus important débat public consacré au temps dans l’histoire de Montréal. Voyant dans l’heure avancée un exemple de la dissociation du temps et du lieu, l’article montre l’importance des dynamiques sociales locales dans l’assignation de sens multiples à la modernité. Conçue comme moyen de faire économiser de l’argent et d’améliorer la qualité de vie des gens, l’idée de l’heure avancée fut pourtant ridiculisée jusqu’à la Première Guerre mondiale, alors que Montréal et une grande partie de l’Amérique du Nord et de l’Europe l’ont adoptée. On l’a toutefois rejetée en tant que mesure nationale après la guerre; plus tard, une grande partie de l’Amérique du Nord et même l’île de Montréal finirent par se transformer en une courtepointe de fuseaux horaires. L’article soutient que les débuts laborieux de l’heure avancée à Montréal s’expliquent par les avantages inégaux associés au changement d’heure, les tensions entre ville et campagne, le système fédéral canadien, les conflits entre plusieurs institutions ethnore-ligieuses, la ténacité du maire de Montréal et le pouvoir économique des entreprises de façonner le temps.

Do You Have the Time? Modernity, Democracy, and the Beginnings of Daylight Saving Time in Montreal, 1907–1928

Abstract: This article looks at the most significant public debate over time in Montreal's history: the beginnings of daylight saving time (1907–1928). Seeing daylight saving time as an example of the disembedding of time from place, the article demonstrates the importance of local social dynamics in the creation of meanings of modernity. Daylight saving time began as an idea to save money and improve people's lives, though it was ridiculed until the First World War, when it was put in place in Montreal and much of North America and Europe. Yet after the war, it was rejected as a national measure, and subsequently much of North America and eventually even the Island of Montreal turned into a patchwork of time zones. The article argues that the difficult beginnings of daylight saving time in Montreal were due to the unequal benefits of changing the clock, rural–urban tensions, the Canadian federal system, conflicts between ethno-religious institutions, Montreal's tenacious mayor, and the economic power of businesses to shape time.

Outdoor Falls in an Urban Context: Winter Weather Impacts and Geographical Variations

Environmental factors associated with winter outdoor falls are poorly understood. This study describes the demographic, spatial and temporal distribution of outdoor falls that occurred in Laval and Montréal Island (Canada) in relation to meteorological conditions. Data on falls, including geographic coordinates, were obtained from ambulance services (December 1, 2008 to january 31, 2009). Meteorological (temperature, precipitation levels) and land use data were used for descriptive analysis and mapping. During the study period, 3270 falls required ambulance interventions, of which 960 occurred outdoors. Most people injured outdoors were under 65 years of age (59%). Mapping showed a concentration of outdoor falls in central neighbourhoods and on commercial streets in Montreal. Three episodes of excess falls, representing 47% of all outdoor falls, were preceded by rain and followed by falling temperatures, or were concomitant with freezing rain. Our results demonstrate for the first time the distribution of outdoor falls in a densely populated urban setting with a northern climate. To promote active transportation, it is essential to take into account the safety of pedestrian travel. Snow removal and de-icing operations in municipalities should prioritize areas with high pedestrian activity.

Neighborhood Social Inequalities in Road Traffic Injuries: The Influence of Traffic Volume and Road Design

We examined the extent to which differential traffic volume and road geometry can explain social inequalities in pedestrian, cyclist, and motor vehicle occupant injuries across wealthy and poor urban areas. We performed a multilevel observational study of all road users injured over 5 years (n=19,568) at intersections (n=17,498) in a large urban area (Island of Montreal, Canada). We considered intersection-level (traffic estimates, major roads, number of legs) and area-level (population density, commuting travel modes, household income) characteristics in multilevel Poisson regressions that nested intersections in 506 census tracts. There were significantly more injured pedestrians, cyclists, and motor vehicle occupants at intersections in the poorest than in the richest areas. Controlling for traffic volume, intersection geometry, and pedestrian and cyclist volumes greatly attenuated the event rate ratios between intersections in the poorest and richest areas for injured pedestrians (-70%), cyclists (-44%), and motor vehicle occupants (-44%). Roadway environment can explain a substantial portion of the excess rate of road traffic injuries in the poorest urban areas.

Indoor thermal condition in urban heat Island – Development of a predictive tool

Urban Heat Island (UHI) effects have caused extensive economic and health related issues to many city residents, especially the most vulnerable such as elderly people living in buildings without air conditioners or mechanical ventilation systems. To reinforce the resiliency of individuals and communities in facing extreme heat event, cities are developing reliable tools to predict the indoor thermal characteristics using available building characteristics, climate data and socio-economical factors.In this study, a novel approach is proposed to predict the indoor thermal conditions in these buildings. First, a measurement campaign is conducted to monitor indoor thermal condition within 55 buildings in most vulnerable regions on the Island of Montreal. Two models, Simplified and Advanced, are developed to predict hourly indoor dry-bulb temperatures. Both models use an advanced Artificial Neural Network (ANN) technique. The Simplified ANN Model generates a correlation between airport weather observations and monitored indoor dry-bulb temperatures. On the other hand, the Advanced Model includes ten influential parameters, which represent the effect of neighboring environment, building characteristics and its usage patterns on the indoor thermal condition. Comparison of these two predictive models is conducted on different levels of simulation and validation. The Advanced Model shows better accuracy in predicting the indoor thermal conditions, thus justifying the use of neighborhood specific parameters to forecast indoor environment condition in an urban heat island area.

Risk of childhood asthma prevalence attributable to residential proximity to major roads in Montreal, Canada.

Exposure to traffic-related air pollutants plays a role in several health outcomes. A large body of evidence tends to link asthma in children with traffic exposure. Increasing asthma prevalence and incidence in children in Canadian cities has been of concern for public health authorities. The following study focuses on estimating the risk of asthma prevalence attributable to residing in proximity to major roads on the Island of Montreal, Canada. Risk functions pertaining to asthma in children and residential proximity to major roads were selected from the literature and applied to Montreal. Asthma prevalence was taken from population-based studies. Population data were retrieved from Canadian census. Exposure was estimated using the proximity to major road and highway category of the Desktop Mapping Technologies Inc. database (DMTI Spatial Inc.). Based on different studies, the percentage of prevalent asthma cases attributable to residing within 50 metres of a major road or highway for children aged 2, 4 and 6 years varied between 2.4% (0-4.3), 5.6% (0.1-8.6) and 5.9% (0.1-9.0). For the 5-7 year age group residing within 75 m of a major road or highway, the percent of cases was 6.4% (2.6-9.3). For children aged 8 to 10 residing within 75 m of a highway only, the percent of cases was 0.7% (0.2-0.9). These numbers represent the best crude estimates and are an indication of a possible range of cases linked to residential proximity to major roads. As there are uncertainties linked to the application of exposure-response functions, these estimates will be reassessed as new evidence is gathered through further research.

Risk of Childhood Asthma Prevalence Attributable to Residential Proximity to Major Roads in Montreal, Canada

Objectives: Exposure to traffic-related air pollutants plays a role in several health outcomes. A large body of evidence tends to link asthma in children with traffic exposure. Increasing asthma prevalence and incidence in children in Canadian cities has been of concern for public health authorities. The following study focuses on estimating the risk of asthma prevalence attributable to residing in proximity to major roads on the Island of Montreal, Canada. Methods: Risk functions pertaining to asthma in children and residential proximity to major roads were selected from the literature and applied to Montreal. Asthma prevalence was taken from population-based studies. Population data were retrieved from Canadian census. Exposure was estimated using the proximity to major road and highway category of the Desktop Mapping Technologies Inc. database (DMTI Spatial Inc.). Results: Based on different studies, the percentage of prevalent asthma cases attributable to residing within 50 metres of a major road or highway for children aged 2, 4 and 6 years varied between 2.4% (0-4.3), 5.6% (0.1-8.6) and 5.9% (0.1-9.0). For the 5-7 year age group residing within 75 m of a major road or highway, the percent of cases was 6.4% (2.6-9.3). For children aged 8 to 10 residing within 75 m of a highway only, the percent of cases was 0.7% (0.2-0.9). Conclusion: These numbers represent the best crude estimates and are an indication of a possible range of cases linked to residential proximity to major roads. As there are uncertainties linked to the application of exposure-response functions, these estimates will be reassessed as new evidence is gathered through further research. Key words: Asthma; attributable risks; children; traffic; air pollutants

Estimating Latent Cycling Trips in Montreal, Canada

About 1.8% of the residents of the Island of Montreal, in Quebec, Canada, ride a bicycle at least once a day during the fall season. These people make nearly 76,990 daily trips, 2.0% of the total number of commuter trips. Of these cyclists, 65% are men, although men represent only 48.1% of residents, and nearly 63.8% are employed, although the employed represent only 45.2% of the island's population. Data from a large-scale travel survey were used to confirm the influence of various factors on bike use. The study showed that men were 1.99 times more likely to make a trip by bike than were women, individuals who lived in a nonmotorized household were 2.35 times more likely to take a trip by bike than were those who lived in motorized households, people who commuted on a sunny day were 1.46 times more likely to travel by bike, and people who lived more than 9.3 mi (15 km) from the downtown area were 0.29 times less likely to travel by bike compared with people who lived nearer. The study also proposed a methodology for estimating latent bicycle trips, that is, the number of car trips that could be made by bike. When a criterion of travel range based on age cohorts and genders was applied, it appeared that about 50.7% of car trips would be made by bike. When more restrictive criteria were used (consideration of trip chains, shopping), it appeared that 18.2% of car trips would be made by bike.

L’accessibilité potentielle aux services de santé mentale à Montréal : approche par les systèmes d’information géographique

Background The inequitable spatial distribution of health resources is a major public health problem because it exacerbates the spatial disparities of access and use of health services. However, efforts to quantify the problem and its consequences on public health have been hampered by a lack of adequate measures and methods. This study explores the spatial potential accessibility to mental health services in a heterogeneous urban environment and evaluates inequities in access to services in deprived areas. Methods The study examines the spatial accessibility to mental health services in the Island of Montreal. All mental health services were geocoded from the six-digital postal code using the software ArcGIS 9.3. Accessibility was assessed through the two step floating catchment area method using the shortest route through a road network more often called reticular distance. This method takes into account the whole population, which is considered as the potential demand. Results In general, accessibility to mental health services seems high in Montreal. It can be seen that at a distance of 1 km, nearly 90% of the territory is accessible. However, we also note that accessibility scores greatly diminish with distance. At 1 km, there are about 10.05 services for 10,000 persons and at 3 km, there is only 1.12 services for 10,000 persons. Over 50% of non-accessible areas are concentrated in the first quartile of deprivation and less than 10% are found in the fourth quartile, indicating good accessibility in severely deprived areas. Conclusion Accessibility to health services will always be the dominant issue debate in developing and undeveloped countries over the next decade. It is therefore urgent to develop technical and methodological tools to study and anticipate areas that may face services’ shortage.

Short-term physiological effects of a xenobiotic mixture on the freshwater mussel Elliptio complanata exposed to municipal effluents

The aim of this study was to investigate the short-term effects of tertiary-treated municipal effluents on the freshwater mussel Elliptio complanata. Caged mussels were immersed during 2 weeks in a river located North of Montreal Island, upstream/downstream the outfall and in one reference site located at the beginning of the Rivière des Prairies. A selection of biomarkers was analyzed to depict changes on various physiological systems: general physiology (mussel viability, condition index and gonado-somatic index), immune status (hemocyte viability, cellularity, phagocytosis efficiency, NK-like cytotoxic activity and lysozyme activity), inflammation (cyclo-oxygenase activity), detoxification (glutathione-S-transferases activity) and vitellogenesis (alkali-labile phosphate level). The analysis of total and fecal coliform counts in water and of heterotrophic bacteria levels in mussel tissues showed that the bacteriological quality of the water strongly decreased from the reference site to the downstream site. This was correlated with a significant loss of weight and an increase of mussel mortality. Cellularity and phagocytosis efficiency were significantly increased in the downstream site compared to the reference site. Though not statistically significant, lysozyme activity was also increased. NK-like cytotoxicity, activity of the pro-inflammatory enzyme COX and the levels of ALP and MT were not significantly changed. Conversely, the municipal effluents induced a significant increase of GST activity in downstream site, indicating a stimulation of detoxification metabolism. Altogether, these results confirm that a short-term exposure to a mixture of bacterial and chemical compounds released by the wastewater treatment plant La Pinière induces adverse physiological effects in E. complanata, as observed with the modulation of immune response and induction of detoxification metabolism.

Comparison of indicators of material circumstances in the context of an epidemiological study

BackgroundSince individual-level income is difficult to collect, investigators often rely on group-based measures derived from census data. No study has assessed the use of residential property values as an indicator of individual material circumstances. We aimed to compare two proxy indicators of material circumstances, one based on residential value and the other on median census tract income, to self-reported household income.MethodsWe used data from a case-control study (1996-2002), restricting analyses to 676 residents of the Island of Montreal for whom the three indicators were available. The degree of discrepancy between the residential value index, census income, and self-reported household income - each in 5 categories - was estimated, along with overall and weighted Kappas.ResultsWhen comparing residential value index and census income to self-reported household income, perfect concordance was observed for 38% and 30% of subjects, respectively; very good concordance, defined as ≤ 1 category difference, was observed for 76% and 69% of subjects, respectively. When compared to self-reported household income, overall and weighted Kappas showed stronger agreement with residential value index (weighted Kappa = 0.37, 95% CI: 0.32, 0.42) than with census income (weighted Kappa = 0.25, 95% CI: 0.20, 0.30).ConclusionsA residential value index may provide a measure of material circumstances that is closer to self-reported household income than the commonly used census income. Each indicator presents advantages and disadvantages, and their choice may depend on study objectives and feasibility.

Optimizing the two-step floating catchment area method for measuring spatial accessibility to medical clinics in Montreal.

BackgroundReducing spatial access disparities to healthcare services is a growing priority for healthcare planners especially among developed countries with aging populations. There is thus a pressing need to determine which populations do not enjoy access to healthcare, yet efforts to quantify such disparities in spatial accessibility have been hampered by a lack of satisfactory measurements and methods. This study compares an optimised and the conventional version of the two-step floating catchment area (2SFCA) method to assess spatial accessibility to medical clinics in Montreal.MethodsWe first computed catchments around existing medical clinics of Montreal Island based on the shortest network distance. Population nested in dissemination areas were used to determine potential users of a given medical clinic. To optimize the method, medical clinics (supply) were weighted by the number of physicians working in each clinic, while the previous year's medical clinic users were computed by ten years age group was used as weighting coefficient for potential users of each medical clinic (demand).ResultsThe spatial accessibility score (SA) increased considerably with the optimisation method. Within a distance of 1 Km, for instance, the maximum clinic accessible for 1,000 persons is 2.4 when the conventional method is used, compared with 27.7 for the optimized method. The t-test indicates a significant difference between the conventional and the optimized 2SFCA methods. Also, results of the differences between the two methods reveal a clustering of residuals when distance increases. In other words, a low threshold would be associated with a lack of precision.ConclusionResults of this study suggest that a greater effort must be made ameliorate spatial accessibility to medical clinics in Montreal. To ensure that health resources are allocated in the interest of the population, health planners and the government should consider a strategy in the sitting of future clinics which would provide spatial access to the greatest number of people.

Perceptions du traitement de l'islam et du monde musulman dans les manuels d'histoire par des enseignants du secondaire au Québec

Perceptions of the Treatment of Islam and the Muslim World in History Textbooks by Secondary School Teachers in QuebecThis article focuses on the ways in which Francophone Quebecois secondary 1 and 2 junior high school teachers adapt and transmit the treatment of Islam and the Muslim world in textbooks used for history and citizenship education. The authors focus on the teachers' capacity to identify factual errors, stereotypes or ethnocentric biases concerning these questions. In order to do this, they analyze fourteen semi-structured interviews carried out with teachers on the island of Montreal, considering dimensions and indicators that relate to their relationship to the formal curriculum, as well as to scholarly and social knowledge of these issues. At the same time, we consider their relationship to the real curriculum or to scholarly knowledge as these are transmitted in real-life learning situations.French Notre article porte sur la manière dont les enseignants du premier cycle du secondaire québécois francophone s'approprient et transmettent le traitement de l'islam et du monde musulman dans le matériel didactique de la discipline d'histoire et d'éducation à la citoyenneté et plus particulièrement, sur leur capacité à identi er les erreurs factuelles, les stéréotypes ou les biais ethnocentriques concernant ces questions. Pour ce faire, nous avons relevé, dans l'analyse des quatorze entretiens semi-directifs menés auprès d'enseignants de l'Ile-de-Montréal, les dimensions et indicateurs portant, d'une part, sur leur rapport au curriculum prescrit, et plus précisément sur leur rapport aux savoirs scolaires, sociaux et parfois de référence sur ces enjeux, et, d'autre part, sur leur rapport au curriculum réel ou aux savoirs scolaires tels que transmis en situation réelle d'apprentissage.

Environmental and social predictors of phosphorus in urban streams on the Island of Montréal, Québec

Researchers have identified the importance of social characteristics for understanding ecological patterns in cities but the use of these characteristics in urban stream research has yet to be fully explored. Urban development is currently the second-largest cause of stream impairment in North America due in part to nutrient loading. However, research into factors that influence nutrient concentrations in urban streams is lacking. We sampled seven streams on the island of Montreal daily to measure phosphorus (P) concentration and P flux in each stream. We then compared stream P concentration and flux to several watershed characteristics commonly used to predict stream nutrients (e.g., watershed imperviousness, land use, existence of a riparian buffer) as well as several socio-economic characteristics of the watersheds (e.g., average home value, median household income). Overall, impervious surface cover and measures of land use were most effective at explaining the variation in P concentration and P flux in streams on the island of Montreal, while the riparian buffer and socio-economic variables were less effective. However, dollars spent on fertilizer per hectare of residential land and percent residential land use became important predictors of stream P concentration when impervious surface cover was removed from the regression model. This suggests that after accounting for the impact of physical watershed characteristics, social factors may be important predictors of urban stream P concentration. The results of our study suggest that more research is needed to determine the role that socio-economic variables play with respect to urban stream P.

Disaggregate Exposure Measures and Injury Frequency Models of Cyclist Safety at Signalized Intersections

This paper proposes a new approach to represent cyclist risk exposure. This approach considers disaggregate motor vehicle and cyclist flows and develops cyclist injury frequency models. Three definitions of risk exposure were used in this research, including aggregated flows, motor vehicle flows aggregated by movement type, and potential conflicts between motor vehicles and cyclists. As an application environment, a large sample of signalized intersections on the island of Montreal, Quebec, Canada, was used, along with data that comprised disaggregate motor vehicle and cyclist flows. Several negative binomial models were fitted to the data. This study showed that cyclist collisions were sensitive to changes in both cyclist and motor vehicle flows. A 10% increase in bicycle flow was associated with a 4.4% increase in the frequency of cyclist injuries. A 10% increase in the total number of motor vehicles that passed through the intersection would result in a 3.4% increase in cyclist injury occurrence. When motor vehicle flows were considered on the basis of movement type, right-turn movements had a great effect on injury occurrence. Similar results, which identified right turns as having the greatest effect on cyclist injuries, were produced when the impact of potential conflicts was determined. The number of bus stops in the proximity of the intersection increased cyclist injury occurrence. Some geometric design factors, such as the presence of a median, parking entrance, and the number of intersection legs, were tested. The effect, however, was found to be statistically nonsignificant.

Associations between Ambient Fine Particulate Levels and Disease Activity in Patients with Systemic Lupus Erythematosus (SLE)

BackgroundSystemic lupus erythematosus (SLE) is a chronic disease of unclear etiology, characterized by an overactive immune system and the production of antibodies that may target normal tissues of many organ systems, including the kidneys. It can arise at any age and occurs mainly in women.ObjectiveOur aim was to evaluate the potential influence of particulate matter (PM) air pollution on clinical aspects of SLE.MethodsWe studied a clinic cohort of SLE patients living on the island of Montreal, followed annually with a structured clinical assessment. We assessed the association between ambient levels of fine PM [median aerodynamic diameter ≤ 2.5 μm (PM2.5)] measured at fixed-site monitoring stations and SLE disease activity measured with the SLE Disease Activity Index, version 2000 (SLEDAI-2K), which includes anti–double-stranded DNA (anti-dsDNA) serum-specific autoantibodies and renal tubule cellular casts in urine, which reflects serious renal inflammation. We used mixed effects regression models that we adjusted for daily ambient temperatures and ozone levels.ResultsWe assessed 237 patients (223 women) who together had 1,083 clinic visits from 2000 through 2007 (mean age at time of first visit, 41.2 years). PM2.5 levels were associated with anti-dsDNA and cellular casts. The crude and adjusted odds ratios (reflecting a 10-μg/m3 increase in PM2.5 averaged over the 48 hr prior to clinical assessment) were 1.26 [95% confidence interval (CI), 0.96–1.65] and 1.34 (95% CI, 1.02–1.77) for anti-dsDNA antibodies and 1.43 (95% CI, 1.05–1.95) and 1.28 (0.92–1.80) for cellular casts. The total SLEDAI-2K scores were not associated with PM2.5 levels.ConclusionsWe provide novel data that suggest that short-term variations in air pollution may influence disease activity in established autoimmune rheumatic disease in humans. Our results add weight to concerns that pollution may be an important trigger of inflammation and autoimmunity.

Limited-stop bus service: an evaluation of an implementation strategy

Transit agencies implement limited-stop (express) bus services as a mean to provide an attractive and competitive transit service. The Societe de transport de Montreal (STM), the transit agency providing service on the Island of Montreal, Canada, implemented a limited-stop service to run parallel to route 67 Saint-Michel, a heavily used bus route. The design process regarding which stops to include in the new service involved an evaluation of several scenarios and an estimation of running time savings. In this paper, we use archived vehicle location and passenger count data to measure changes in on-time performance and running times, and to compare these changes to previous estimates through a before-and-after study. In addition, an on-site survey is conducted to measure the riders’ perception of time savings. Implementing a limited-stop service yielded to 4.6 minutes savings in running time for the new limited service; meanwhile, the existing regular service experienced an increase of 0.8 minute in average running time, an increase that could be due to a new smart card system introduced in the same period. The running time savings for the limited-stop service fall in the expected estimates made by the research team, which strengthens our trust in the methodology used to select stops and to estimate savings. Finally, the study shows that riders are generally satisfied with the new service. They also tend to overestimate the savings associated with the implementation of the new limited-stop service by 4 to 7 minutes more than the actual savings.

Parasite fauna of Etheostoma nigrum (Percidae: Etheostomatinae) in localities of varying pollution stress in the St. Lawrence River, Quebec, Canada

Parasite communities were examined in johnny darters (Etheostoma nigrum) collected from five localities in the St. Lawrence River in southwestern Quebec: two reference localities, one polluted locality upstream of the Island of Montreal and downstream of industrial and agricultural activity, and two polluted localities downstream of the Island of Montreal in the plume from the wastewater treatment facility. Twenty-four helminth species were found. Fish from the upstream polluted locality had the highest parasite species richness and total parasite numbers, and fish from the downstream polluted localities the lowest. Nonmetric multivariate analyses were conducted using square-root-transformed Bray-Curtis dissimilarity index. An analysis of similarity, dendrogram of centroids, and a permutational multivariate analysis of variance with contrasts all showed that fish from the reference localities had different parasite community composition than those from the polluted localities, and fish from the upstream polluted locality had different parasite communities than fish from the downstream polluted localities. Differences between reference and polluted localities were mainly due to higher abundances of the brain-encysting trematode, Ornithodiplostomum sp., at the reference localities. Differences between upstream and downstream polluted localities were mainly due to a higher diversity and abundance of trematodes in fish at the upstream locality.