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Suspended sediment quality in Hamilton Harbour has been assessed as part of a long-term monitoring study (1987–2012). Sampling locations reflected a range of shoreline activities and sources of chemical contamination to the harbour. Temporal data showed a trend toward decreasing levels of contamination by polycyclic aromatic hydrocarbons and polychlorinated biphenyls over the period from the late 1980s to the early 1990s, with a subsequent leveling off over the next two decades. The highest concentrations of both contaminants were detected in areas impacted by industrial activities along the southern shoreline and Windermere Arm, and deep-water areas of the harbour where fine-grained sediments ultimately accumulate. Areas of the harbor discharging residential or rural parts of the watershed exhibited generally lower levels of contamination. In addition to the relatively higher contaminant levels, areas along the southern shoreline and Windermere Arm characterized by historical industrial activities and associated contaminated sediments exhibited chemical profiles indicating an impact on suspended sediment and bottom sediment quality throughout the harbour. Continued monitoring after scheduled remedial activities should provide an assessment of the overall efficacy of management actions to improve sediment quality in Hamilton Harbour. [ABSTRACT FROM AUTHOR]

We made observations from vertical moorings of thermistors and current meters in Lake Ontario to study the spring thermal bar circulation, its effect in inhibiting the horizontal mixing, and spatial and temporal variability of vertical mixing during this period. Thermal bar progression rates were compared with two analytical models; both produced overestimates during the early part of the thermal bar and underestimates during the late spring. In a zone between the shore and the thermal bar, currents were influenced by the local wind stress and flowed in a counterclockwise direction. The mean cross-shore flows in the nearshore zone were reduced during the thermal bar period. The alongshore horizontal exchange coefficients were higher than cross-shore exchange coefficients. During the thermal bar period, the magnitude of both alongshore and cross-shore exchange coefficients decreased when the bar was still within middepth (<40 m); when it was further offshore, the thermal bar did not have any significant effect on alongshore exchange coefficients, but cross-shore exchanges decreased marginally. The vertical exchange coefficients were high in the water column because of convective mixing during the thermal bar period. During the evolution of spring thermal bar, the vertical mixing decreased considerably in the nearshore regions under stable stratification, whereas the high vertical mixing levels continued in the offshore region for a longer period. [ABSTRACT FROM AUTHOR]

The alternate strategy of open-lake discharge may alleviate the need for unusually stringent treatment needed to meet water quality goals of the Hamilton Harbour Remedial Action Plan (RAP). The latest update of the RAP recommended a study of the possibility of offshore discharges. A study conducted for the City of Burlington has proposed a location for outfall in Lake Ontario. This paper utilizes a combination of physical limnological data and mathematical models to predict the waste plume characteristics for the proposed outfall in the lake. Near-field dilutions obtained from a mixing zone model show that, for treated effluents with a discharge condition of 2 m³/s at the proposed outfall site at Burlington, the dilution ratios are in the range of 13:1 to 28:1 for weak to moderate currents during summer stratification. Winter dilution ratios increased to 21:1 to 96:1 for moderate currents. The recommended site for openlake outfall provides acceptable near-field dilutions for treated effluents under typical lake currents and density structure. The extension of outfall to a location farther offshore is only marginally beneficial. With the proposed Burlington outfall location and discharge conditions, no far-field contamination is observed near the beaches or nearby water intakes for typical summer and winter conditions. Thus, this study indicates that by discharging the treated sewage from an outfall in Lake Ontario it is possible to achieve the Hamilton Harbour RAP goals. [ABSTRACT FROM AUTHOR]

The circulation and exchange processes during summer stratification were examined using time-series data of horizontal velocity, temperature, and dissolved oxygen profiles during 2004 and 2005 in the mid-central basin of Lake Erie. The current and temperature spectra showed a prominent peak at around 18 h, indicating the presence of clockwise rotating inertial waves. The mean bottom currents were strong (>0.1 m s-1) and flowed in opposite direction to winds because of the surface pressure gradient due to wind set-up. The general range of horizontal exchange coefficients in the central basin is 0.2-1.2 m² s-1. Vertical exchange coefficients varied from 1 x 10-5 to 1 x 10-4 m² s-1. The high values usually occurred in the surface layer because of surface winds. The source of turbulent energy is current shear due to near-inertial oscillations in and above the thermocline and shearing stress due to the effect of mean currents and wave-induced motions during energetic wind events at the lake bottom. During strong wind episodes significant wave-induced currents were observed close to the bottom. The short-term oxygen depletion rates varied considerably between +0.87 mg L-1 d-1 and -1.16 mg L-1 d-1 in 2004 mainly because of physical processes in the central basin. When the hypolimnion depth is sufficiently thick (4 m), shortterm changes in dissolved oxygen concentrations were partly due to vertical mixing and partly due to horizontal transport and mixing. [ABSTRACT FROM AUTHOR]

Introduction: In 2012, the Ontario government launched Health Links (HL), which was designed to integrate care for patients with multimorbidity and complex needs who are high users of health services. This study evaluated perceptions of family and friend caregivers of patients enrolled in the HL program. Research questions included: What are (a) characteristics of caregivers of patients enrolled in HL (b) caregivers' perceptions of the program in relation to HL's guiding principles (patient and family-centred care, accessibility, coordination of services, and continuity of care and care provider) and (c) caregivers' perceptions of the impact of HL on themselves and their care recipient?, Methods: This study involved a survey and qualitative, semi-structured interviews. HL guiding principles (patient and family-centered care, accessibility, coordination of services, and continuity) guided the analysis., Results: Twenty-seven surveys and 16 qualitative interviews were completed. Caregivers reported high levels of strain [Modified Caregiver Strain Index (MCSI) 15.5 (SD 7.03)], mild anxiety [Generalized Anxiety Disorder (GAD 7), 9.6 (SD 6.64)] and depression [Center for Epidemiological Studies Depression Scale (CES-D 10), 11.9 (SD 8.72)]. Regarding the guiding principles, most caregivers had a copy of the HL patient's care plan, although some caregivers noted that their needs were not included in the plan, nor were they asked for input. Caregivers found the program's home and phone visits accessible. Despite minimum wait times for community-based services, other access barriers persisted, (i.e., out-of-pocket costs). HL provided well-coordinated patient services, although some perceived that there was poor team communication. Caregiver perceptions varied on the quality of care provided. Provider continuity provided caregiver relief and patient support: A lack of continuity was related to changes in care coordinators and weekend staff and attrition., Conclusions: Caregivers of HL patients appreciated patient- and family-centred, accessible, consistent, coordinated and team-based approaches in care. Providers and decision-makers are urged to ensure that programs aimed at high system users address these core concepts while addressing caregivers' needs., Competing Interests: The authors have declared that no competing interests exist.

Background: Public health systems in Canada have undergone significant policy renewal over the last decade in response to threats to the public's health, such as severe acute respiratory syndrome. There is limited research on how public health policies have been implemented or what has influenced their implementation. This paper explores policy implementation in two exemplar public health programs -chronic disease prevention and sexually-transmitted infection prevention - in Ontario, Canada. It examines public health service providers', managers' and senior managements' perspectives on the process of implementation of the Ontario Public Health Standards 2008 and factors influencing implementation., Methods: Public health staff from six health units representing rural, remote, large and small urban settings were included. We conducted 21 focus groups and 18 interviews between 2010 (manager and staff focus groups) and 2011 (senior management interviews) involving 133 participants. Research assistants coded transcripts and researchers reviewed these; the research team discussed and resolved discrepancies. To facilitate a breadth of perspectives, several team members helped interpret the findings. An integrated knowledge translation approach was used, reflected by the inclusion of academics as well as decision-makers on the team and as co-authors., Results: Front line service providers often were unaware of the new policies but managers and senior management incorporated them in operational and program planning. Some participants were involved in policy development or provided feedback prior to their launch. Implementation was influenced by many factors that aligned with Greenhalgh and colleagues' empirically-based Diffusion of Innovations in Service Organizations Framework. Factors and related components that were most clearly linked to the OPHS policy implementation were: attributes of the innovation itself; adoption by individuals; diffusion and dissemination; the outer context - interorganizational networks and collaboration; the inner setting - implementation processes and routinization; and, linkage at the design and implementation stage., Conclusions: Multiple factors influenced public health policy implementation. Results provide empirical support for components of Greenhalgh et al's framework and suggest two additional components - the role of external organizational collaborations and partnerships as well as planning processes in influencing implementation. These are important to consider by government and public health organizations when promoting new or revised public health policies as they evolve over time. A successful policy implementation process in Ontario has helped to move public health towards the new vision.