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1.
J Fish Biol ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679466

RESUMO

The migratory behavior of Atlantic salmon (Salmo salar) post-smolts in coastal waters is poorly understood. In this collaborative study, 1914 smolts, from 25 rivers, in four countries were tagged with acoustic transmitters during a single seasonal migration. In total, 1105 post-smolts entered the marine study areas and 438 (39.6%) were detected on a network of 414 marine acoustic receivers and an autonomous underwater vehicle. Migration pathways (defined as the shortest distance between two detections) of up to 575 km and over 100 days at sea were described for all 25 populations. Post-smolts from different rivers, as well as individuals from the same river, used different pathways in coastal waters. Although difficult to generalize to all rivers, at least during the year of this study, no tagged post-smolts from rivers draining into the Irish Sea were detected entering the areas of sea between the Hebrides and mainland Scotland, which is associated with a high density of finfish aquaculture. An important outcome of this study is that a high proportion of post-smolts crossed through multiple legislative jurisdictions and boundaries during their migration. This study provides the basis for spatially explicit assessment of the impact risk of coastal pressures on salmon during their first migration to sea.

2.
J Fish Biol ; 104(1): 265-283, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37843923

RESUMO

The freshwater phase of the first seaward migration of juvenile Atlantic salmon (Salmo salar) is relatively well understood when compared with our understanding of the marine phase of their migration. In 2021, 1008 wild and 60 ranched Atlantic salmon smolts were tagged with acoustic transmitters in 12 rivers in England, Scotland, Northern Ireland and Ireland. Large marine receiver arrays were deployed in the Irish Sea at two locations: at the transition of the Irish Sea into the North Atlantic between Ireland and Scotland, and between southern Scotland and Northern Ireland, to examine the early phase of the marine migration of Atlantic salmon smolts. After leaving their natal rivers' post-smolt migration through the Irish Sea was rapid with minimum speeds ranging from 14.03 to 38.56 km.day-1 for Atlantic salmon smolts that entered the Irish Sea directly from their natal river, to 9.69-39.94 km.day-1 for Atlantic salmon smolts that entered the Irish Sea directly from their natal estuary. Population minimum migration success through the study area was strongly correlated with the distance of travel, populations further away from the point of entry to the open North Atlantic exhibited lower migration success. Post-smolts from different populations experienced different water temperatures on entering the North Atlantic. This was largely driven by the timing of their migration and may have significant consequences for feeding and ultimately survivorship. The influence of water currents on post-smolt movement was investigated using data from previously constructed numerical hydrodynamic models. Modeled water current data in the northern Irish Sea showed that post-smolts had a strong preference for migrating when the current direction was at around 283° (west-north-west) but did not migrate when exposed to strong currents in other directions. This is the most favorable direction for onward passage from the Irish Sea to the continental shelf edge current, a known accumulation point for migrating post-smolts. These results strongly indicate that post-smolts migrating through the coastal marine environment are: (1) not simply migrating by current following (2) engage in active directional swimming (3) have an intrinsic sense of their migration direction and (4) can use cues other than water current direction to orientate during this part of their migration.


Assuntos
Rios , Salmo salar , Animais , Sinais (Psicologia) , Migração Animal , Água
3.
Proc Natl Acad Sci U S A ; 117(36): 22303-22310, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817535

RESUMO

Penguins are the only extant family of flightless diving birds. They currently comprise at least 18 species, distributed from polar to tropical environments in the Southern Hemisphere. The history of their diversification and adaptation to these diverse environments remains controversial. We used 22 new genomes from 18 penguin species to reconstruct the order, timing, and location of their diversification, to track changes in their thermal niches through time, and to test for associated adaptation across the genome. Our results indicate that the penguin crown-group originated during the Miocene in New Zealand and Australia, not in Antarctica as previously thought, and that Aptenodytes is the sister group to all other extant penguin species. We show that lineage diversification in penguins was largely driven by changing climatic conditions and by the opening of the Drake Passage and associated intensification of the Antarctic Circumpolar Current (ACC). Penguin species have introgressed throughout much of their evolutionary history, following the direction of the ACC, which might have promoted dispersal and admixture. Changes in thermal niches were accompanied by adaptations in genes that govern thermoregulation and oxygen metabolism. Estimates of ancestral effective population sizes (Ne ) confirm that penguins are sensitive to climate shifts, as represented by three different demographic trajectories in deeper time, the most common (in 11 of 18 penguin species) being an increased Ne between 40 and 70 kya, followed by a precipitous decline during the Last Glacial Maximum. The latter effect is most likely a consequence of the overall decline in marine productivity following the last glaciation.


Assuntos
Evolução Molecular , Genoma/genética , Spheniscidae , Animais , Regiões Antárticas , Austrália , Mudança Climática , Ecossistema , Estudo de Associação Genômica Ampla , Nova Zelândia , Filogenia , Seleção Genética/genética , Spheniscidae/classificação , Spheniscidae/genética , Spheniscidae/fisiologia
5.
J Fish Biol ; 96(2): 316-326, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31647569

RESUMO

Using data from wild Atlantic salmon Salmo salar returning to spawn in seven Scottish rivers, we developed a model of fecundity based on individual body size and key developmental traits. We used a novel approach to model selection which maximises predictive accuracy for application to target river stocks to select the best from a suite of Bayesian hierarchical models. This approach aims to ensure the optimal model within the candidate set includes covariates that best predict out-of-sample data to estimate fecundity in areas where no direct observations are available. In addition to body size, the final model included the developmental characteristics of age at smolting and years spent at sea. Using two independent long-term monitoring datasets, the consequences of ignoring these characteristics was revealed by comparing predictions from the best model with models that omitted them.


Assuntos
Fertilidade , Salmo salar/anatomia & histologia , Animais , Teorema de Bayes , Tamanho Corporal , Feminino , Pesqueiros/organização & administração , Modelos Teóricos , Fenótipo
6.
Environ Sci Technol ; 51(16): 8933-8943, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28650153

RESUMO

Cyanobacterial harmful algal blooms (CyanoHABs) have serious adverse effects on human and environmental health. Herein, we developed a modeling framework that predicts the effect of climate change on cyanobacteria concentrations in large reservoirs in the contiguous U.S. The framework, which uses climate change projections from five global circulation models, two greenhouse gas emission scenarios, and two cyanobacterial growth scenarios, is unique in coupling climate projections with a hydrologic/water quality network model of the contiguous United States. Thus, it generates both regional and nationwide projections useful as a screening-level assessment of climate impacts on CyanoHAB prevalence as well as potential lost recreation days and associated economic value. Our projections indicate that CyanoHAB concentrations are likely to increase primarily due to water temperature increases tempered by increased nutrient levels resulting from changing demographics and climatic impacts on hydrology that drive nutrient transport. The combination of these factors results in the mean number of days of CyanoHAB occurrence ranging from about 7 days per year per waterbody under current conditions, to 16-23 days in 2050 and 18-39 days in 2090. From a regional perspective, we find the largest increases in CyanoHAB occurrence in the Northeast U.S., while the greatest impacts to recreation, in terms of costs, are in the Southeast.


Assuntos
Mudança Climática , Proliferação Nociva de Algas , Cianobactérias , Água Doce , Humanos , Estados Unidos , Qualidade da Água
8.
Milbank Q ; 90(2): 311-46, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22709390

RESUMO

CONTEXT: Participatory research (PR) is the co-construction of research through partnerships between researchers and people affected by and/or responsible for action on the issues under study. Evaluating the benefits of PR is challenging for a number of reasons: the research topics, methods, and study designs are heterogeneous; the extent of collaborative involvement may vary over the duration of a project and from one project to the next; and partnership activities may generate a complex array of both short- and long-term outcomes. METHODS: Our review team consisted of a collaboration among researchers and decision makers in public health, research funding, ethics review, and community-engaged scholarship. We identified, selected, and appraised a large-variety sample of primary studies describing PR partnerships, and in each stage, two team members independently reviewed and coded the literature. We used key realist review concepts (middle-range theory, demi-regularity, and context-mechanism-outcome configurations [CMO]) to analyze and synthesize the data, using the PR partnership as the main unit of analysis. FINDINGS: From 7,167 abstracts and 591 full-text papers, we distilled for synthesis a final sample of twenty-three PR partnerships described in 276 publications. The link between process and outcome in these partnerships was best explained using the middle-range theory of partnership synergy, which demonstrates how PR can (1) ensure culturally and logistically appropriate research, (2) enhance recruitment capacity, (3) generate professional capacity and competence in stakeholder groups, (4) result in productive conflicts followed by useful negotiation, (5) increase the quality of outputs and outcomes over time, (6) increase the sustainability of project goals beyond funded time frames and during gaps in external funding, and (7) create system changes and new unanticipated projects and activities. Negative examples illustrated why these outcomes were not a guaranteed product of PR partnerships but were contingent on key aspects of context. CONCLUSIONS: We used a realist approach to embrace the heterogeneity and complexity of the PR literature. This theory-driven synthesis identified mechanisms by which PR may add value to the research process. Using the middle-range theory of partnership synergy, our review confirmed findings from previous PR reviews, documented and explained some negative outcomes, and generated new insights into the benefits of PR regarding conflicts and negotiation between stakeholders, program sustainability and advancement, unanticipated project activity, and the generation of systemic change.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Avaliação de Programas e Projetos de Saúde , Fortalecimento Institucional , Comportamento Cooperativo , Pesquisa sobre Serviços de Saúde , Humanos , Seleção de Pessoal
9.
BMC Public Health ; 12: 452, 2012 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-22712716

RESUMO

BACKGROUND: Climate change is among the major challenges for health this century, and adaptation to manage adverse health outcomes will be unavoidable. The risks in Ontario - Canada's most populous province - include increasing temperatures, more frequent and intense extreme weather events, and alterations to precipitation regimes. Socio-economic-demographic patterns could magnify the implications climate change has for Ontario, including the presence of rapidly growing vulnerable populations, exacerbation of warming trends by heat-islands in large urban areas, and connectedness to global transportation networks. This study examines climate change adaptation in the public health sector in Ontario using information from interviews with government officials. METHODS: Fifty-three semi-structured interviews were conducted, four with provincial and federal health officials and 49 with actors in public health and health relevant sectors at the municipal level. We identify adaptation efforts, barriers and opportunities for current and future intervention. RESULTS: Results indicate recognition that climate change will affect the health of Ontarians. Health officials are concerned about how a changing climate could exacerbate existing health issues or create new health burdens, specifically extreme heat (71%), severe weather (68%) and poor air-quality (57%). Adaptation is currently taking the form of mainstreaming climate change into existing public health programs. While adaptive progress has relied on local leadership, federal support, political will, and inter-agency efforts, a lack of resources constrains the sustainability of long-term adaptation programs and the acquisition of data necessary to support effective policies. CONCLUSIONS: This study provides a snapshot of climate change adaptation and needs in the public health sector in Ontario. Public health departments will need to capitalize on opportunities to integrate climate change into policies and programs, while higher levels of government must improve efforts to support local adaptation and provide the capacity through which local adaptation can succeed.


Assuntos
Mudança Climática , Governo Local , Saúde Pública , Gestão de Riscos/organização & administração , Geografia Médica , Humanos , Ontário , Pesquisa Qualitativa
10.
Soc Sci Med ; 75(6): 1067-77, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22703884

RESUMO

The potential impacts of climate change on human health in sub-Saharan Africa are wide-ranging, complex, and largely adverse. The region's Indigenous peoples are considered to be at heightened risk given their relatively poor health outcomes, marginal social status, and resource-based livelihoods; however, little attention has been given to these most vulnerable of the vulnerable. This paper contributes to addressing this gap by taking a bottom-up approach to assessing health vulnerabilities to climate change in two Batwa Pygmy communities in rural Uganda. Rapid Rural Appraisal and PhotoVoice field methods complemented by qualitative data analysis were used to identify key climate-sensitive, community-identified health outcomes, describe determinants of sensitivity at multiple scales, and characterize adaptive capacity of Batwa health systems. The findings stress the importance of human drivers of vulnerability and adaptive capacity and the need to address social determinants of health in order to reduce the potential disease burden of climate change.


Assuntos
População Negra/estatística & dados numéricos , Mudança Climática , Disparidades nos Níveis de Saúde , Saúde da População Rural/estatística & dados numéricos , Populações Vulneráveis , Adulto , Feminino , Humanos , Masculino , Fotografação , Pesquisa Qualitativa , Fatores de Risco , Fatores Socioeconômicos , Uganda
11.
Glob Health Promot ; 18(2): 45-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21744664

RESUMO

Participatory research (PR) experts believe that increased community and stakeholder participation in research augments program pertinence, quality, outcome, sustainability, uptake, and transferability. There is, however, a dearth of assessments and measurement tools to demonstrate the contribution of participation in health research and interventions. One systematic review of PR, conducted for the Agency for Health Research and Quality (AHRQ), provided no conclusive evidence concerning the benefits of community participation to enhance research and health outcomes. To overcome methodological gaps and barriers of the AHRQ review, we propose to conduct a systematic realist review, which can be understood as a theory-driven qualitative review capable of capturing the often complex, diffuse and obtuse evidence concerning participation. Reviewing how PR mechanisms and contextual factors mediate and moderate outcomes, the review will generate and test hypotheses (middle-range theories) conceptualizing the benefits of participation and will portray the manner and circumstances in which participation influences outcomes.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Avaliação de Programas e Projetos de Saúde , Promoção da Saúde , Estados Unidos , United States Agency for Healthcare Research and Quality
12.
Implement Sci ; 6: 24, 2011 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-21418604

RESUMO

BACKGROUND: Participatory Research (PR) entails the co-governance of research by academic researchers and end-users. End-users are those who are affected by issues under study (e.g., community groups or populations affected by illness), or those positioned to act on the knowledge generated by research (e.g., clinicians, community leaders, health managers, patients, and policy makers). Systematic reviews assessing the generalizable benefits of PR must address: the diversity of research topics, methods, and intervention designs that involve a PR approach; varying degrees of end-user involvement in research co-governance, both within and between projects; and the complexity of outcomes arising from long-term partnerships. METHODS: We addressed the above mentioned challenges by adapting realist review methodology to PR assessment, specifically by developing inductively-driven identification, selection, appraisal, and synthesis procedures. This approach allowed us to address the non-uniformity and complexity of the PR literature. Each stage of the review involved two independent reviewers and followed a reproducible, systematic coding and retention procedure. Retained studies were completed participatory health interventions, demonstrated high levels of participation by non-academic stakeholders (i.e., excluding studies in which end-users were not involved in co-governing throughout the stages of research) and contained detailed descriptions of the participatory process and context. Retained sets are being mapped and analyzed using realist review methods. RESULTS: The librarian-guided search string yielded 7,167 citations. A total of 594 citations were retained after the identification process. Eighty-three papers remained after selection. Principle Investigators (PIs) were contacted to solicit all companion papers. Twenty-three sets of papers (23 PR studies), comprising 276 publications, passed appraisal and are being synthesized using realist review methods. DISCUSSION: The systematic and stage-based procedure addressed challenges to PR assessment and generated our robust understanding of complex and heterogeneous PR practices. To date, realist reviews have focussed on evaluations of relatively uniform interventions. In contrast our PR search yielded a wide diversity of partnerships and research topics. We therefore developed tools to achieve conceptual clarity on the PR field, as a beneficial precursor to our theoretically-driven synthesis using realist methods. Findings from the ongoing review will be provided in forthcoming publications.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Avaliação de Resultados em Cuidados de Saúde , Projetos de Pesquisa , Medicina Baseada em Evidências , Humanos
13.
Environ Manage ; 39(1): 1-11, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17106795

RESUMO

Current political conditions, primarily budgetary uncertainty, and the related reluctance to make funding commitments for future generations, have raised questions about the costs of conservation and environmental protection that have not previously been asked. As Federal investments are scrutinized and budgets become ever more constrained, the costs associated with environmental requirements could begin to be of greater importance and to influence decisions on Federal projects. In response to concerns about the U.S. Army Corps of Engineers (Corps) spending under the Endangered Species Act (P.L. 93-205) (ESA), a limited investigation was performed to determine the accuracy of reported Corps expenditures. The investigation showed that, for particular groups of species, actual conservation costs for threatened and endangered species may be twice the amounts previously reported in the annual ESA expenditure reporting to the U.S. Fish and Wildlife Service. In light of this finding, the Corps has sought a means to provide more accurate and consistent reporting of expenditures for addressing threatened and endangered species. A Species Costs Template (template) has been developed to identify the types and magnitude of costs related to the ESA and to counteract the impediments (legal, institutional, and practical) to underreporting costs. The template will be used by the Corps for reporting ESA costs beginning with Fiscal Year 2005 (FY05) (reported in January 2006). Five broad categories of expenditures (effects determination costs, ESA protection and conservation costs, equipment costs, opportunity costs, and other species costs) are identified by the template.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Custos e Análise de Custo , Regulamentação Governamental , Biodiversidade , Ecologia , Gastos em Saúde , Humanos , Dinâmica Populacional , Política Pública
14.
Am J Med ; 119(9): 791-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16945615

RESUMO

PURPOSE: Patient experience varies with the currently available colon imaging tests, including air contrast barium enema, computed tomographic colonography, and colonoscopy. We examined differences in patient experience with colon imaging tests and whether they varied with gender, age, and race. SUBJECTS AND METHODS: Patients with fecal occult blood, hematochezia, iron-deficiency anemia, or a family history of colon cancer underwent air contrast barium enema followed 7 to 14 days later by computed tomographic colonography and colonoscopy. Validated patient experience questionnaires that measured the experience for each test and a separate questionnaire that obtained an overall summary measure were administered after testing. Eleven patient experiences including pain, embarrassment, difficulty with bowel preparation, and satisfaction with tests were examined. RESULTS: A total of 614 subjects completed all 3 imaging tests. The test most patients were willing to repeat was colonoscopy; it also was reported to be the least painful procedure. Patients were least satisfied with air contrast barium enema, and fewer would undergo air contrast barium enema compared with computed tomographic colonography or colonoscopy. There were limited racial and gender differences in perceptions of the tests. Younger adults perceived air contrast barium enema to be more painful than older adults. CONCLUSION: Taking into account a wide variety of patient experience measures, patients preferred colonoscopy to air contrast barium enema and computed tomographic colonography. This finding has important implications for physicians considering different colon imaging tests.


Assuntos
Sulfato de Bário , Colonografia Tomográfica Computadorizada/métodos , Colonoscopia/métodos , Enema/métodos , Satisfação do Paciente , Colo/diagnóstico por imagem , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Meios de Contraste/farmacologia , Coleta de Dados , Humanos , Inquéritos e Questionários
17.
Plant Physiol ; 134(3): 995-1005, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14963244

RESUMO

A seed marks the transition between two developmental states; a plant is an embryo during seed formation, whereas it is a seedling after emergence from the seed. Two factors have been identified in Arabidopsis that play a role in establishment of repression of the embryonic state: PKL (PICKLE), which codes for a putative CHD3 chromatin remodeling factor, and gibberellin (GA), a plant growth regulator. Previous observations have also suggested that PKL mediates some aspects of GA responsiveness in the adult plant. To investigate possible mechanisms by which PKL and GA might act to repress the embryonic state, we further characterized the ability of PKL and GA to repress embryonic traits and reexamined the role of PKL in mediating GA-dependent responses. We found that PKL acts throughout the seedling to repress expression of embryonic traits. Although the ability of pkl seedlings to express embryonic traits is strongly induced by inhibiting GA biosynthesis, it is only marginally responsive to abscisic acid and SPY (SPINDLY), factors that have previously been demonstrated to inhibit GA-dependent responses during germination. We also observed that pkl plants exhibit the phenotypic hallmarks of a mutation in a positive regulator of a GA response pathway including reduced GA responsiveness and increased synthesis of bioactive GAs. These observations indicate that PKL may mediate a subset of GA-dependent responses during shoot development.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/embriologia , Arabidopsis/genética , Genes de Plantas , Arabidopsis/efeitos dos fármacos , Sequência de Bases , DNA Helicases , DNA de Plantas/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Germinação , Giberelinas/biossíntese , Giberelinas/farmacologia , Fenótipo , Plantas Geneticamente Modificadas , Proteínas Repressoras/genética
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