9 research outputs found

    Where the wild things are: Seasonal variation in caribou distribution in relation to climate change

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    In this study, we develop a method to analyse the relationships between seasonal caribou distribution and climate, to estimate how climatic conditions affect interactions between humans and caribou, and ultimately to predict patterns of distribution relative to climate change. Satellite locations for the Porcupine (Rangifer tarandus granti) and Bathurst (R. t. groenlandicus) caribou herds were analysed for eight ecologically-defined seasons. For each season, two levels of a key environmental factor influencing caribou distribution were identified, as well as the best climate data available to indicate the factor's annual state. Satellite locations were grouped according to the relevant combination of season and environmental factor. Caribou distributions were compared for opposing environmental factors; this comparison was undertaken relative to hunting access for the Porcupine Herd and relative to exposure to mining activity for the Bathurst Herd. Expected climate trends suggest an overall increase in access to Porcupine caribou for Aklavik (NWT) hunters during the winter and rut seasons, for Venetie (Alaska) hunters during midsummer and fall migration and for Arctic Village (Alaska) during midsummer. Arctic Village may experience reduced availability with early snowfalls in the fall, but we expect there to be little directional shift in the spring migration patterns. For the Bathurst Herd, we expect that fewer caribou would be exposed to the mines during the winter, while more caribou would be exposed to the combined Ekati and Diavik mining zone in the early summer and to the Lupin-Jericho mining zone during the fall migration. If changes in climate cause an increased presence of caribou in the mining sites, monitoring and mitigation measures may need to be intensified

    An integrated assessment of Porcupine caribou seasonal distribution, movements, and habitat preferences for regional land use planning in northern Yukon Territory, Canada

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    This study was undertaken to improve understanding of Porcupine caribou herd distribution, movements, and habitat preferences to assist with developing a regional land use plan for the North Yukon Planning Region, Yukon Territory. Three different methods were used to identify current and historical patterns of caribou distribution and habitat preferences within the region to prioritize conservation areas. Two of the approaches focused on incorporating information on caribou distribution and migrations from scientific and local knowledge, while the third focused on identifying and mapping habitats suitable for supporting caribou. Local knowledge dating back to the 1930s and two decades of satellite telemetry data confirmed that most of the planning region is used by the Porcupine caribou herd and highlighted areas of concentrated use. Maps of suitable winter habitat derived from expert opinion ratings of habitat use did not agree with the other information sources. The local knowledge and satellite telemetry analyses were used to identify spatially explicit priority areas for caribou conservation and the results were applied to develop conservation recommendations for a draft regional land use plan. The plan will be submitted to government approval bodies for review in the spring of 2007. The success in implementing conservation strategies for the Porcupine caribou herd will be reviewed and evaluated following adoption of a final approved plan

    Abstracts from the NIHR INVOLVE Conference 2017

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    Where the wild things are: Seasonal variation in caribou distribution in relation to climate change

    Get PDF
    In this study, we develop a method to analyse the relationships between seasonal caribou distribution and climate, to estimate how climatic conditions affect interactions between humans and caribou, and ultimately to predict patterns of distribution relative to climate change. Satellite locations for the Porcupine (Rangifer tarandus granti) and Bathurst (R. t. groenlandicus) caribou herds were analysed for eight ecologically-defined seasons. For each season, two levels of a key environmental factor influencing caribou distribution were identified, as well as the best climate data available to indicate the factor's annual state. Satellite locations were grouped according to the relevant combination of season and environmental factor. Caribou distributions were compared for opposing environmental factors; this comparison was undertaken relative to hunting access for the Porcupine Herd and relative to exposure to mining activity for the Bathurst Herd. Expected climate trends suggest an overall increase in access to Porcupine caribou for Aklavik (NWT) hunters during the winter and rut seasons, for Venetie (Alaska) hunters during midsummer and fall migration and for Arctic Village (Alaska) during midsummer. Arctic Village may experience reduced availability with early snowfalls in the fall, but we expect there to be little directional shift in the spring migration patterns. For the Bathurst Herd, we expect that fewer caribou would be exposed to the mines during the winter, while more caribou would be exposed to the combined Ekati and Diavik mining zone in the early summer and to the Lupin-Jericho mining zone during the fall migration. If changes in climate cause an increased presence of caribou in the mining sites, monitoring and mitigation measures may need to be intensified

    An integrated assessment of Porcupine caribou seasonal distribution, movements, and habitat preferences for regional land use planning in northern Yukon Territory, Canada

    Get PDF
    This study was undertaken to improve understanding of Porcupine caribou herd distribution, movements, and habitat preferences to assist with developing a regional land use plan for the North Yukon Planning Region, Yukon Territory. Three different methods were used to identify current and historical patterns of caribou distribution and habitat preferences within the region to prioritize conservation areas. Two of the approaches focused on incorporating information on caribou distribution and migrations from scientific and local knowledge, while the third focused on identifying and mapping habitats suitable for supporting caribou. Local knowledge dating back to the 1930s and two decades of satellite telemetry data confirmed that most of the planning region is used by the Porcupine caribou herd and highlighted areas of concentrated use. Maps of suitable winter habitat derived from expert opinion ratings of habitat use did not agree with the other information sources. The local knowledge and satellite telemetry analyses were used to identify spatially explicit priority areas for caribou conservation and the results were applied to develop conservation recommendations for a draft regional land use plan. The plan will be submitted to government approval bodies for review in the spring of 2007. The success in implementing conservation strategies for the Porcupine caribou herd will be reviewed and evaluated following adoption of a final approved plan

    Adjuvant pembrolizumab versus placebo in resected stage III melanoma (EORTC 1325-MG/KEYNOTE-054): distant metastasis-free survival results from a double-blind, randomised, controlled, phase 3 trial

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    International audienceBackground: The European Organisation for Research and Treatment of Cancer (EORTC) 1325/KEYNOTE-054 trial assessed pembrolizumab versus placebo in patients with resected high-risk stage III melanoma. At 15-month median follow-up, pembrolizumab improved recurrence-free survival (hazard ratio [HR] 0路57 [98路4% CI 0路43-0路74], p1 mm), IIIB, or IIIC (without in-transit metastasis), and with an Eastern Cooperative Oncology Group performance status of 0 or 1 were eligible. Patients were randomly assigned (1:1) via a central interactive voice response system to receive intravenous pembrolizumab 200 mg or placebo every 3 weeks for up to 18 doses or until disease recurrence or unacceptable toxicity. Randomisation was stratified according to disease stage and region, using a minimisation technique, and clinical investigators, patients, and those collecting or analysing the data were masked to treatment assignment. The two coprimary endpoints were recurrence-free survival in the intention-to-treat (ITT) population and in patients with PD-L1-positive tumours. The secondary endpoint reported here was distant metastasis-free survival in the ITT and PD-L1-positive populations. This study is registered with ClinicalTrials.gov, NCT02362594, and EudraCT, 2014-004944-37.Findings: Between Aug 26, 2015, and Nov 14, 2016, 1019 patients were assigned to receive either pembrolizumab (n=514) or placebo (n=505). At an overall median follow-up of 42路3 months (IQR 40路5-45路9), 3路5-year distant metastasis-free survival was higher in the pembrolizumab group than in the placebo group in the ITT population (65路3% [95% CI 60路9-69路5] in the pembrolizumab group vs 49路4% [44路8-53路8] in the placebo group; HR 0路60 [95% CI 0路49-0路73]; p<0路0001). In the 853 patients with PD-L1-positive tumours, 3路5-year distant metastasis-free survival was 66路7% (95% CI 61路8-71路2) in the pembrolizumab group and 51路6% (46路6-56路4) in the placebo group (HR 0路61 [95% CI 0路49-0路76]; p<0路0001). Recurrence-free survival remained longer in the pembrolizumab group 59路8% (95% CI 55路3-64路1) than the placebo group 41路4% (37路0-45路8) at this 3路5-year follow-up in the ITT population (HR 0路59 [95% CI 0路49-0路70]) and in those with PD-L1-positive tumours 61路4% (56路3-66路1) in the pembrolizumab group and 44路1% (39路2-48路8) in the placebo group (HR 0路59 [95% CI 0路49-0路73]).Interpretation: Pembrolizumab adjuvant therapy provided a significant and clinically meaningful improvement in distant metastasis-free survival at a 3路5-year median follow-up, which was consistent with the improvement in recurrence-free survival. Therefore, the results of this trial support the indication to use adjuvant pembrolizumab therapy in patients with resected high risk stage III cutaneous melanoma.Funding: Merck Sharp & Dohme

    Adjuvant pembrolizumab versus placebo in resected stage III melanoma (EORTC 1325-MG/KEYNOTE-054): health-related quality-of-life results from a double-blind, randomised, controlled, phase 3 trial

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    International audienceBackground: The European Organisation for Research and Treatment of Cancer (EORTC) 1325-MG/KEYNOTE-054 trial in patients with resected, high-risk stage III melanoma demonstrated improved recurrence-free survival with adjuvant pembrolizumab compared with placebo (hazard ratio 0路57 [98路4% CI 0路43-0路74]; p<0路0001). This study reports the results from the health-related quality-of-life (HRQOL) exploratory endpoint.Methods: This double-blind, randomised, controlled, phase 3 trial was done at 123 academic centres and community hospitals across 23 countries. Patients aged 18 years or older with previously untreated histologically confirmed stage IIIA, IIIB, or IIIC resected cutaneous melanoma, and an Eastern Cooperative Oncology Group performance status score of 1 or 0 were eligible. Patients were randomly assigned (1:1) using a central interactive voice-response system on the basis of a minimisation technique stratified for stage and geographic region to receive intravenously 200 mg pembrolizumab or placebo. Treatment was administered every 3 weeks for 1 year, or until disease recurrence, unacceptable toxicity, or death. The primary endpoint of the trial was recurrence-free survival (reported elsewhere). HRQOL was a prespecified exploratory endpoint, with global health/quality of life (GHQ) over 2 years measured by the EORTC QLQ-C30 as the primary analysis. Analyses were done in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT02362594, and EudraCT, 2014-004944-37, and long-term follow-up is ongoing.Findings: Between Aug 26, 2015, and Nov 14, 2016, 1019 patients were assigned to pembrolizumab (n=514) or placebo (n=505). Median follow-up was 15路1 months (IQR 12路8-16路9) at the time of this analysis. HRQOL compliance was greater than 90% at baseline, greater than 70% during the first year, and greater than 60% thereafter for both groups. Because of low absolute compliance numbers at later follow-up, the analysis was truncated to week 84. Baseline GHQ scores were similar between groups (77路55 [SD 18路20] in the pembrolizumab group and 76路54 [17路81] in the placebo group) and remained stable over time. The difference in average GHQ score between the two groups over the 2 years was -2路2 points (95% CI -4路3 to -0路2). The difference in average score during treatment was -1路1 points (95% CI -3路2 to 0路9) and the difference in average score after treatment was -2路2 points (-4路8 to 0路4). These differences are within the 5-point clinical relevance threshold for the QLQ-C30 and are therefore clinically non-significant.Interpretation: Pembrolizumab does not result in a clinically significant decrease in HRQOL compared with placebo when given as adjuvant therapy for patients with resected, high-risk stage III melanoma. These results support the use of adjuvant pembrolizumab in this setting
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