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1.
Ecol Evol ; 12(3): e8716, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35342604

RESUMEN

Reconstruction of historical relationships between geographic regions within a species' range can indicate dispersal patterns and help predict future responses to shifts in climate. Ascaphus truei (coastal tailed frog) is an indicator species of the health of forests and perennial streams in the Coastal and Cascade Mountains of the Pacific Northwest of North America. We used two genetic techniques-microsatellite and genotype-by-sequencing (GBS)-to compare the within-region genetic diversity of populations near the northern extent of the species' range (British Columbia, Canada) to two geographic regions in British Columbia and two in Washington, USA, moving toward the core of the range. Allelic richness and heterozygosity declined substantially as latitude increased. The northernmost region had the lowest mean expected heterozygosities for both techniques (microsatellite, M = 0.20, SE = 0.080; GBS, M = 0.025, SE = 0.0010) and the southernmost region had the highest (microsatellite, M = 0.88, SE = 0.054; GBS, M = 0.20, SE = 0.0029). The northernmost regions (NC and MC) clustered together in population structure models for both genetic techniques. Our discovery of reduced diversity may have important conservation and management implications for population connectivity and the response of A. truei to climate change.

2.
Nat Commun ; 13(1): 595, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35105881

RESUMEN

Habitat loss is the leading cause of the global decline in biodiversity, but the influence of human pressure within the matrix surrounding habitat fragments remains poorly understood. Here, we measure the relationship between fragmentation (the degree of fragmentation and the degree of patch isolation), matrix condition (measured as the extent of high human footprint levels), and the change in extinction risk of 4,426 terrestrial mammals. We find that the degree of fragmentation is strongly associated with changes in extinction risk, with higher predictive importance than life-history traits and human pressure variables. Importantly, we discover that fragmentation and the matrix condition are stronger predictors of risk than habitat loss and habitat amount. Moreover, the importance of fragmentation increases with an increasing deterioration of the matrix condition. These findings suggest that restoration of the habitat matrix may be an important conservation action for mitigating the negative effects of fragmentation on biodiversity.


Asunto(s)
Ecosistema , Extinción Biológica , Animales , Biodiversidad , Humanos , Mamíferos
3.
Accid Anal Prev ; 118: 207-213, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29598877

RESUMEN

To gain a better understanding of the dynamics of moose-vehicle collisions, we analyzed 96 videos of moose-vehicle interactions recorded by vehicle dash-mounted cameras (Dash Cams) that had been posted to the video-sharing website YouTube™. Our objective was to determine the effects of road conditions, season and weather, moose behavior, and driver response to actual collisions compared to near misses when the collision was avoided. We identified 11 variables that were consistently observable in each video and that we hypothesized would help to explain a collision or near miss. The most parsimonious logistic regression model contained variables for number of moose, sight time, vehicle slows, and vehicle swerves (AICcw = 0.529). This model had good predictive accuracy (AUC = 0.860, SE = 0.041). The only statistically significant variable from this model that explained the difference between moose-vehicle collisions and near misses was 'Vehicle slows'. Our results provide no evidence that road surface conditions (dry, wet, ice or snow), roadside habitat type (forested or cleared), the extent to which roadside vegetation was cleared, natural light conditions (overcast, clear, twilight, dark), season (winter, spring and summer, fall), the presence of oncoming traffic, or the direction from which the moose entered the roadway had any influence on whether a motorist collided with a moose. Dash Cam videos posted to YouTube™ provide a unique source of data for road safety planners trying to understand what happens in the moments just before a moose-vehicle collision and how those factors may differ from moose-vehicle encounters that do not result in a collision.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Ciervos , Ambiente , Tiempo (Meteorología) , Animales , Desaceleración , Humanos , Internet , Modelos Logísticos , Grabación en Video
4.
Cancer ; 123 Suppl 24: 5037-5058, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29205308

RESUMEN

BACKGROUND: In the first CONCORD study, 5-year survival for patients with diagnosed with rectal cancer between 1990 and 1994 was <60%, with large racial disparities noted in the majority of participating states. We have updated these findings to 2009 by examining population-based survival by stage of disease at the time of diagnosis, race, and calendar period. METHODS: Data from the CONCORD-2 study were used to compare survival among individuals aged 15 to 99 years who were diagnosed in 37 states encompassing up to 80% of the US population. We estimated net survival up to 5 years after diagnosis correcting for background mortality with state-specific and race-specific life table. Survival estimates were age-standardized with the International Cancer Survival Standard weights. We present survival estimates by race (all, black, and white) for 2001 through 2003 and 2004 through 2009 to account for changes in collecting the data for Surveillance, Epidemiology, and End Results Summary Stage 2000. RESULTS: There was a small increase in 1-year, 3-year, and 5-year net survival between 2001-2003 (84.6%, 70.7%, and 63.2%, respectively), and 2004-2009 (85.1%, 71.5%, and 64.1%, respectively). Black individuals were found to have lower 1-year, 3-year, and 5-year survival than white individuals in both periods; the absolute difference in survival between black and white individuals declined only for 5-year survival. Black patients had lower 5-year survival than whites at each stage at the time of diagnosis in both time periods. CONCLUSIONS: There was little improvement noted in net survival for patients with rectal cancer, with persistent disparities noted between black and white individuals. Additional investigation is needed to identify and implement effective interventions to ensure the consistent and equitable use of high-quality screening, diagnosis, and treatment to improve survival for patients with rectal cancer. Cancer 2017;123:5037-58. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Neoplasias del Recto/mortalidad , Sistema de Registros , Población Blanca/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias del Recto/etnología , Neoplasias del Recto/patología , Estados Unidos/epidemiología , Adulto Joven
5.
Ecol Evol ; 7(23): 10266-10277, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29238553

RESUMEN

Predation risk is a driver of species' distributions. Animals can increase risk avoidance in response to fluctuations in predation risk, but questions remain regarding individual variability and the capacity to respond to changes in spatial risk across human-altered landscapes. In northeast British Columbia, Canada, boreal caribou populations declined as roads and seismic lines have increased, which are theorized to increase gray wolf predation. Our goal was to model risk and to evaluate individual variability and the development of risk perception by examining individual risk avoidance in response to reproductive status and age. We used locations from collared caribou and wolves to identify landscape features associated with the risk of a potential wolf-caribou encounter and risk of being killed given an encounter. We built resource selection functions to estimate individual responses to risk. We used general linear regressions to evaluate individual risk and linear feature avoidance as a function of age and reproductive status (calf or no calf). Linear features increased the risk of encounter. Older caribou and caribou with calves demonstrated stronger avoidance of the risk of encounter and roads, but weaker avoidance in late summer to the risk of being killed relative to younger and calf-less individuals. Mechanisms explaining the inverse relationships between the risk of encounter and risk of being killed are uncertain, but it is conceivable that caribou learn to avoid the risk of encounter and roads. Responses by females with vulnerable calves to the risk of encounter and risk of being killed might be explained by a trade-off between these two risk types and a prioritization on the risk of encounter. Despite the capacity to alter their responses to risk, the global decline in Rangifer populations (caribou and wild reindeer) suggests these behaviors are insufficient to mitigate the impacts of anthropogenic disturbances.

6.
Environ Manage ; 60(3): 484-495, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28497173

RESUMEN

Resource development projects typically result in monitoring programs that fail to fully consider the values and participation of surrounding communities. Also, monitoring protocols for single environmental values can be insufficient for addressing the cumulative impacts of resource development. Community-based environmental monitoring (CBEM) has emerged as a way to meaningfully include local citizens in the decision-making process and assessment of the development of natural resources. Our research explored how to develop effective and sustainable CBEM. Interviews were conducted with staff from 15 CBEM programs established across Canada to identify criteria of what constitutes effective CBEM. Results demonstrate that CBEM offers an effective, locally adapted, and culturally applicable approach to facilitate community participation in natural resource management and to track environmental change. Benefits of CBEM include: locally relevant monitoring protocols, inclusion of cumulative impacts, better informed decision-making, and increased awareness and collaboration amongst community, governments, and proponents. Challenges associated with CBEM are cost, capacity, longevity, distribution of results, and establishing credibility. This research validates the use of CBEM for improving resource management.


Asunto(s)
Participación de la Comunidad , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , Canadá , Toma de Decisiones , Humanos , Investigación , Encuestas y Cuestionarios
7.
Ecol Evol ; 7(3): 845-854, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28168021

RESUMEN

Human presence in natural environments is often a source of stress that is perceived by large ungulates as an increased risk of predation. Alternatively, disturbance induced by hikers creates a relatively predator-free space that may serve as a refuge. We measured the behavioral responses of female caribou to disturbance associated with the presence of hikers during summer in the Gaspésie National Park. We used those data to determine whether caribou responded negatively to human activity (i.e., the predation risk hypothesis) or whether human activity resulted in a decrease in the magnitude of perceived risk (i.e., the refuge hypothesis). Female caribou with a calf spent nearly half of their time feeding, regardless of the presence of a trail or the number of hikers. They also decreased their vigilance near trails when the number of hikers increased. Conversely, lone females fed less frequently and almost doubled the time invested in vigilance under the same circumstances. However, both groups of females moved away from trails during the day, especially in the presence of hikers. We demonstrated that risk avoidance was specific to the maternal state of the individual. Lactating females accommodated the presence of hikers to increase time spent foraging and nutritional intake, providing support for the refuge hypothesis. Alternatively, lone females with lower energetic requirements and no maternal investment in a vulnerable calf appeared less tolerant to risk, consistent with the predation risk hypothesis. Synthesis and applications: Hikers influenced the vigilance-feeding trade-off in caribou, underlining the importance of appropriate management of linear structures and human activities, especially across the critical habitat of endangered species. Even if some individuals seemed to benefit from human presence, this behavioral adaptation was not sufficient to reduce annual calf mortality associated with predation.

8.
J Anim Ecol ; 85(1): 11-20, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25786026

RESUMEN

Habitats have substantial influence on the distribution and abundance of animals. Animals' selective movement yields their habitat use. Animals generally are more abundant in habitats that are selected most strongly. Models of habitat selection can be used to distribute animals on the landscape or their distribution can be modelled based on data of habitat use, occupancy, intensity of use or counts of animals. When the population is at carrying capacity or in an ideal-free distribution, habitat selection and related metrics of habitat use can be used to estimate abundance. If the population is not at equilibrium, models have the flexibility to incorporate density into models of habitat selection; but abundance might be influenced by factors influencing fitness that are not directly related to habitat thereby compromising the use of habitat-based models for predicting population size. Scale and domain of the sampling frame, both in time and space, are crucial considerations limiting application of these models. Ultimately, identifying reliable models for predicting abundance from habitat data requires an understanding of the mechanisms underlying population regulation and limitation.


Asunto(s)
Distribución Animal , Ecosistema , Animales , Modelos Biológicos , Movimiento , Densidad de Población
9.
Ecol Appl ; 22(6): 1838-51, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23092020

RESUMEN

Climate change is occurring at an accelerated rate in the Arctic. Insect harassment may be an important link between increased summer temperature and reduced body condition in caribou and reindeer (both Rangifer tarandus). To examine the effects of climate change at a scale relevant to Rangifer herds, we developed monitoring indices using weather to predict activity of parasitic insects across the central Arctic. During 2007-2009, we recorded weather conditions and used carbon dioxide baited traps to monitor activity of mosquitoes (Culicidae), black flies (Simuliidae), and oestrid flies (Oestridae) on the post-calving and summer range of the Bathurst barren-ground caribou (Rangifer tarandus groenlandicus) herd in Northwest Territories and Nunavut, Canada. We developed statistical models representing hypotheses about effects of weather, habitat, location, and temporal variables on insect activity. We used multinomial logistic regression to model mosquito and black fly activity, and logistic regression to model oestrid fly presence. We used information theory to select models to predict activity levels of insects. Using historical weather data, we used hindcasting to develop a chronology of insect activity on the Bathurst range from 1957 to 2008. Oestrid presence and mosquito and black fly activity levels were explained by temperature. Wind speed, light intensity, barometric pressure, relative humidity, vegetation, topography, location, time of day, and growing degree-days also affected mosquito and black fly levels. High predictive ability of all models justified the use of weather to index insect activity. Retrospective analyses indicated conditions favoring mosquito activity declined since the late 1950s, while predicted black fly and oestrid activity increased. Our indices can be used as monitoring tools to gauge potential changes in insect harassment due to climate change at scales relevant to caribou herds.


Asunto(s)
Cambio Climático , Culicidae , Dípteros , Insectos/fisiología , Reno , Tiempo (Meteorología) , Animales , Mordeduras y Picaduras de Insectos/veterinaria , Modelos Biológicos
10.
J Anim Ecol ; 81(1): 284-95, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21950373

RESUMEN

1. Macroparasites may be a major factor shaping animal behaviour. Tundra ecosystems inhabited by caribou and reindeer (Rangifer tarandus) are known for large concentrations of ectoparasites including mosquitoes (Culicidae) and black flies (Simuliidae), as well as endoparasitic oestrid flies (Oestridae). 2. Increased intensity and duration of insect harassment because of climatic warming is hypothesized as a potential factor in recent declines of Rangifer across the circumpolar north. Although there is a well-observed relationship between insect harassment and caribou/reindeer behaviour, the influence of ecto- relative to endoparasitic species is unclear. Climatic changes may favour the activity patterns, distribution or abundance of certain insect species; thus, understanding differential effects on the behaviour of Rangifer is important. 3. We recorded caribou behaviour using group scan and focal sampling methods, while simultaneously trapping insects and recording weather conditions on the postcalving/summer range of the Bathurst barren-ground caribou herd in Northwest Territories and Nunavut, Canada, during 2007-2009. 4. We developed statistical model sets representing hypotheses about the effects of insects, weather, habitat/location, and date/time on caribou behaviour. We used multinomial logistic regression models to explore factors affecting the relative dominance of behaviour types within groups of caribou and fractional multinomial logistic regression models to determine factors influencing time allocation by individual caribou. We examined changes in feeding intensity using fractional logistic regression. 5. Relative dominance of insect avoidance behaviour within caribou groups and time allocation to insect avoidance by individual caribou increased when oestrid flies were present or black flies were active at moderate-high levels. Mosquito activity had relatively little effect on caribou behaviour. Time spent feeding was reduced by the greatest degree when all three insect types were present in combination. Feeding intensity was influenced to a greater extent by the accumulation of growing degree days over the course of the postcalving/summer season than by insect activity. Changes in Arctic systems that increase the activity/abundance of ecto- and endoparasites could have implications for the productivity of Rangifer populations.


Asunto(s)
Conducta Animal , Dípteros/fisiología , Reno/fisiología , Animales , Culicidae/fisiología , Ecosistema , Conducta Alimentaria , Modelos Logísticos , Modelos Biológicos , Territorios del Noroeste , Nunavut , Simuliidae/fisiología , Especificidad de la Especie , Factores de Tiempo , Tiempo (Meteorología)
11.
Cancer Epidemiol ; 35(2): 126-31, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20952269

RESUMEN

BACKGROUND: One measure of the accuracy of cancer mortality statistics is the concordance between cancer defined as the underlying cause of death from death certificates and cancer diagnoses recorded in central, population-based cancer registries. Previous studies of such concordance are outdated. OBJECTIVE: To characterize the accuracy of cancer mortality statistics from the concordance between cancer cause of death and primary cancer site at diagnosis. DESIGN: Central cancer registry records from California, Colorado, and Idaho in the U.S. were linked with state vital statistics data and evaluated by demographic and tumor information across 79 site categories. A retrospective arm (confirmation rate per 100 deaths) compared death certificate data from 2002 to 2004 with cancer registry diagnoses from 1993 to 2004, while a prospective arm (detection rate per 100 deaths) compared cancer registry diagnoses from 1993 to 1995 with death certificate data from 1993 to 2004 by International Statistical Classification of Diseases and Related Health Problems (ICD) version used to code deaths. RESULTS: With n=265,863 deaths where cancer was recorded as the underlying cause based on the death certificate, the overall confirmation rate for ICD-10 was 82.8% (95% confidence interval [CI], 82.6-83.0%), the overall detection rate for ICD-10 was 81.0% (95% CI, 80.4-81.6%), and the overall detection rate for ICD-9 was 85.0% (95% CI, 84.8-85.2%). These rates varied across primary sites, where some rates were <50%, some were 95% or greater, and notable differences between confirmation and detection rates were observed. CONCLUSIONS: Important unique information on the quality of cancer mortality data obtained from death certificates is provided. In addition, information is provided for future studies of the concordance of primary cancer site between population-based cancer registry data and data from death certificates, particularly underlying causes of death coded in ICD-10.


Asunto(s)
Neoplasias/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Certificado de Defunción , Femenino , Humanos , Masculino , Persona de Mediana Edad , Programa de VERF , Estados Unidos/epidemiología , Adulto Joven
12.
Minn Med ; 86(11): 34-9, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14658557

RESUMEN

Anorexia nervosa and bulimia nervosa are serious, life-threatening illnesses that often require several years of treatment. Although classified as mental health diagnoses, they are associated with significant medical consequences and have the highest rate of premature death of any mental health diagnosis. They also are associated with the highest rate of short- and long-term physiological complications. Eating disorders disproportionately affect young women. With early intervention and aggressive treatment, affected adolescents and young adults can recover and be free of the disorder. This article reviews the difficulties in recognizing that a patient has an eating disorder and the signs and symptoms providers should look for. It also discusses our current understanding of the causes of eating disorders as well as current treatment methods, which involve a multidisciplinary approach.


Asunto(s)
Anorexia Nerviosa/diagnóstico , Bulimia/diagnóstico , Adolescente , Adulto , Anorexia Nerviosa/etiología , Anorexia Nerviosa/mortalidad , Anorexia Nerviosa/terapia , Bulimia/etiología , Bulimia/mortalidad , Bulimia/terapia , Causas de Muerte , Enfermedad Crónica , Diagnóstico Diferencial , Femenino , Humanos , Cuidados a Largo Plazo , Masculino , Minnesota , Grupo de Atención al Paciente , Pronóstico , Factores de Riesgo
13.
Oecologia ; 127(4): 590-602, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-28547497

RESUMEN

We examined the foraging behavior of woodland caribou (Rangifer tarandus caribou) relative to the spatial and temporal heterogeneity of their environment. We assessed (1) whether caribou altered their behavior over time while making trade-offs between forage abundance and accessibility; and (2) whether foraging decisions were consistent across spatial scales (i.e., as scale increased, similar decision criteria were used at each scale). We discuss whether caribou adjusted their behavior to take advantage of changing forage availability through time and space. At the scale of the feeding site (as revealed by discriminant function analyses), caribou in both forested and alpine (above tree-line) environments selected sites where the biomass of particular lichen species was greatest and snow the least deep. Caribou did not select those species with the highest nutritional value (i.e., digestible protein and energy) in either area. Where snow depth, density, and hardness limited access to terrestrial lichens in the forest, caribou foraged instead at those trees with the greatest amount of arboreal lichen. Selection of lichen species and the influence of snow differed across time, indicating that in this system the abundance or accessibility of forage temporally influenced foraging behavior. A path analysis of forest data and multiple regression analysis of alpine data were used to test the hypothesis that variables important at the scale of the feeding site explained foraging effort at the scale of the patch. For forest patches, our hypothesized model reliably explained foraging effort, but not all variables that were statistically important at the scale of the feeding site were significant predictors at the scale of the patch. For alpine patches, our hypothesized model did not explain a statistically significant portion of the variation in the number of feeding sites within the patch, and none of the individual variables from the feeding site remained statistically significant at the patch scale. The incongruity between those variables important at the scale of the feeding site and those important at the patch showed that spatial scale affects the foraging decisions of woodland caribou. At the scale of the landscape, there was a trade-off between forage abundance and accessibility. Relative to the alpine environment, caribou in the forest foraged at feeding sites and patches with greater amounts of less variably distributed lichen, but deeper less variable snow depths. Considering the behavioral plasticity of woodland caribou, there may be no distinct advantage to foraging in one landscape over the other.

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