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An overview of chemical and biological oceanographic conditions in the Gulf of St. Lawrence in 2021 is presented as part of the Atlantic Zone Monitoring Program (AZMP). AZMP data as well as data from regional monitoring programs are analyzed and presented in relation to long-term means in the context of a warming trend that began in 2010. These long-term means are typically calculated using 1999-2020 as a reference period. Oxygen levels at 300 m reached a record-low concentration in the northwest and central Gulf and in Cabot Strait. Nitrate inventories in the surface layer (0-50 m) of the Gulf were either near or below normal, with record-low levels in the Estuary and northwest Gulf. Mid-layer nitrate inventories (50-150 m) were also below normal in these two subregions, but near or above normal in the other regions. In the bottom layer (150 m-bottom), positive anomalies were found in all Gulf regions with record-high inventories everywhere but in the Estuary. Positive deep nitrate anomalies have been observed regularly since 2012 in the Cabot Strait and the central Gulf and are associated with intrusions of warm and salty waters, but they have been less common in the Estuary over the last decade. The recent increase in the nitrate inventory of the bottom layer is mostly associated with negative anomalies of the N:P ratio and positive anomalies of the Si:N ratio. Annual inventories of vertically integrated chlorophyll a (chl a; 0-100 m) were near normal in all regions except for the Estuary and northwest Gulf, where they were above normal. In these two subregions, the second highest inventories of chl a were observed during fall. Most regions have regularly shown above-normal chl a inventories during fall since about 2014. In contrast, phytoplankton biomass derived from satellite data mostly showed negative annual and fall anomalies in most of the ocean colour polygons over the last four years, including several record-low values in 2021. Spring bloom metric anomalies indicated that the bloom was generally on time but was slightly less intense than normal. Zooplankton biomass was either near or below normal everywhere in the Gulf, with a record-low level in the Estuary/northwest Gulf region. Calanus finmarchicus annual abundance was near normal except at Rimouski station, where it was slightly above normal. C. hyperboreus abundance showed widespread negative anomalies, including a record-low level in the northeast Gulf. Small calanoids were at record-high abundances at Rimouski station and in the Estuary/northwest Gulf region, and their abundances were also above normal in the Magdalen Shallows, and at the Shediac Valley station. Abundances of warm-water copepods were also at record-high levels in the Estuary/northwest Gulf region as well as in northeast Gulf and Magdalen Shallows, and abundances were also above normal in other regions. Cold-water copepod abundances were either near normal or above normal, and record-high values were observed at both high-frequency monitoring stations. The characterization of C. finmarchicus phenology at Rimouski station indicated that the peak of early copepodite stages (CI-CIII) was the earliest and longest-lasting peak ever recorded. [ABSTRACT FROM AUTHOR]

This article describes a districting study undertaken for the Cote-des-Neiges local community health clinic in Montreal. A territory must be partitioned into six districts by suitably grouping territorial basic units. Five districting criteria must be respected: indivisibility of basic units, respect for borough boundaries, connectivity, visiting personnel mobility, and workload equilibrium. The last two criteria are combined into a single objective function and the problem is solved by means of a tabu search technique that iteratively moves a basic unit to an adjacent district or swaps two basic units between adjacent districts. The problem was solved and the clinic management confirmed its satisfaction after a 2 year implementation period. Keywords: districting; community health clinic; multi-criteria optimization; tabu search

In the general routing problem, the aim is to determine a least cost traversal of a subset of edges, arcs and vertices of a graph. The problem can be transformed into an equivalent traveling salesman problem or rural postman problem and solved optimally. Computational results are reported. Keywords: generalized routing problem; traveling salesman problem; rural postman problem; generalized traveling salesman problem

An overview of chemical and biological oceanographic conditions in the Gulf of St. Lawrence in 2020 is presented as part of the Atlantic Zone Monitoring Program (AZMP). AZMP data as well as data from regional monitoring programs are analyzed and presented in relation to long-term means in the context of a strong warming event that began in 2010. These long-term means are now calculated on data from 1999-2020 (1999-2015 in earlier reports). Oxygen levels at 300 m reached a record low concentration in the Estuary and at Rimouski station. Nitrate inventories in the surface layer (0-50 m) of the Gulf were either near or slightly above normal. Nitrate midlayer inventories (50-150 m) were above normal in the northern and central Gulf, while they were close to normal in Magdalen Shallows and Cabot Strait. In the bottom layer (150 m-bottom), positive nitrate anomalies were found in all Gulf regions. Positive deep nitrate anomalies have been observed regularly since 2012 in Cabot Strait and the central Gulf in association with intrusions of warm and salty waters, but they have been rare in the Estuary over the last decade. The recent increase in the nitrate inventory of the bottom layer is mostly associated with negative anomalies of the N:P ratio and positive anomalies of the Si:N ratio. There were strong positive anomalies of vertically integrated chlorophyll a (chl a; 0-100 m) during late summer in the northeast Gulf, during fall in the Estuary, and, to a lesser extent, in the central Gulf during both seasons. Elsewhere, vertically integrated phytoplankton biomass was close to normal except in Cabot Strait, where it was below normal. Most regions have shown either near-normal or above-normal chl a inventories during fall since about 2014. In contrast, phytoplankton biomass derived from satellite data showed negative annual and fall anomalies in most of the ocean colour averaging areas over the last three years. Spring bloom metrics were mostly near normal, except for high bloom amplitudes and magnitudes in the Magdalen Shallows and Cabot Strait boxes. Zooplankton biomass was close to normal almost everywhere in the Gulf; it was only below normal in the central Gulf/Cabot Strait region. Calanus finmarchicus, C. hyperboreus, and large calanoid abundances were also generally close to normal, except that C. hyperboreus abundance was above normal in the northwest Gulf and below normal on the Magdalen Shallows. Small calanoid abundances were near normal everywhere despite record low abundance of Pseudocalanus spp. on the Magdalen Shallows and low abundances in the northwest Gulf and at Rimouski station. Abundances of warm-waterassociated copepods were slightly above normal in most regions and at a record high on the Magdalen Shallows. The lack of sampling during spring precluded characterization of Calanus finmarchicus phenology at Rimouski station this year. [ABSTRACT FROM AUTHOR]

Background: In 2017, the international European Men-who-have-sex-with-men Internet Survey (EMIS-2017) collected data from 50 countries, including Canada for the first time. Objective: To provide an overview of the Canadian EMIS-2017 data to describe the sexually transmitted and other bloodborne infection (STBBI) related needs of gay, bisexual and other men who have sex with men (gbMSM). Methods: The EMIS-2017 questionnaire was an updated version of EMIS-2010. It included self-reported sociodemographic data, experience of discrimination, mental health and substance use, knowledge of preexposure prophylaxis (PrEP) for HIV, sexual practices and history of STBBI testing and diagnosis. Analysis was largely descriptive. Results: Of the 6,059 respondents from Canada, 5,165 participants met the inclusion criteria for this analysis. The majority of participants were born in Canada (79.3%); and over half of the respondents (56.7%) were under the age of 39. In terms of discrimination related to their attraction to other men, participants reported high levels of intimidation (31.9%), verbal abuse (22.1%) and physical violence (1.5%) in the previous year. Regarding mental health, 23.9% had a moderate to severe depression/anxiety score. Almost two-thirds (64.1%) indicated substance use and one-fifth (21.5%) reported chemsex (or the use of stimulant drugs to make sex more intense or last longer). Only 8.4% of participants reported use of PrEP for HIV; however, 51.7% reported being likely to use PrEP if it was available and affordable. Sexual practices, such as condom use, varied by PrEP use with 91.3% of men using PrEP reporting condomless anal intercourse (CAI) compared with 71.5% of men not on PrEP. In terms of STBBI testing, 1.5% reported being diagnosed with hepatitis C and 9.0% reported an HIV diagnosis. Of those with an HIV diagnosis, most were on treatment (99.1%) and had an undetectable viral load (96.7%). Conclusion: gbMSM in Canada experienced stigma, discrimination and mental health problems; substance use was high as were high-risk sexual practices, such as CAI, among some groups of men. There was a gap between the proportion of men who were interested in PrEP and those who actually used it; and comprehensive STBBI testing was low [ABSTRACT FROM AUTHOR]

An overview of chemical and biological oceanographic conditions in the Gulf of St. Lawrence (GSL) in 2017 is presented as part of the Atlantic Zone Monitoring Program (AZMP). AZMP data as well as data from regional monitoring programs are analyzed and presented in relation to long-term means in the context of a strong warming event that began in 2010. Oxygen levels at 300 m reached their lowest concentration measured so far in several GSL regions during 2017. Negative anomalies in deep O2 concentration were especially strong in central GSL and the Cabot Strait region. Nitrate inventories in the surface layer (0-50 m) were generally near normal everywhere in the GSL all year round. However, they were above normal in deep waters of eastern GSL (eGSL), which has been observed since 2012 and is associated with intrusions of warm and salty waters. Vertically integrated chlorophyll a (chl a; 0-100 m) was below normal in western GSL (wGSL) and above normal in southern GSL (sGSL) during summer and fall. In sGSL, the positive chl a anomaly measured in situ was actually the strongest recorded since 2002. However, according to satellite imagery, the spring bloom amplitude was generally below normal everywhere in the GSL, including sGSL. Satellite estimates show a near-normal surface chl a annual mean throughout the GSL despite low spring biomass. Dinoflagellate abundance reached a record low at Rimouski station, while it was above normal at Shediac Valley as were flagellates and ciliates at this station. In 2017, zooplankton biomass was below average everywhere in the GSL, but the main zooplankton functional groups and species abundances were all above normal in eGSL with the exception of Calanus hyperboreus. In wGSL and sGSL, C. finmarchicus, Pseudocalanus spp., and total copepod abundances showed negative anomalies. It is the first time since 2012-2013 that negative anomalies have been recorded for Pseudocalanus spp. Moreover, the widespread positive anomalies of small calanoid abundance that have been observed since 2008 were restricted to Rimouski station and eGSL in 2017. Higher-than-normal abundances of copepod species associated with warm water were again observed in 2017, continuing a trend observed since 2011. Development of C. finmarchicus was delayed at Rimouski station in 2017, unlike observations in recent years. Some of these phytoplankton and zooplankton dynamics could reflect the influence of a St. Lawrence freshwater runoff well above the normal in May and June 2017 and of year-round warmer-thannormal deep waters. [ABSTRACT FROM AUTHOR]