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1.
Sci Rep ; 14(1): 11472, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769407

RESUMO

Fin whales, Balenoptera physalus, are capital breeders, having the potential to separate breeding and feeding both spatially and temporally. Fin whales occur throughout the Northwest Atlantic, but stock structure and seasonal movements remain unclear. By deploying satellite transmitters on 28 individuals, we examine movement patterns within and beyond the Gulf of St. Lawrence (GSL), Canada, and challenge the current understanding of stock structure. Eight individuals left the GSL in autumn, with five tags persisting into January. Migration patterns of these whales showed considerable variation in timing and trajectory, with movements extending south to 24°N, and thus beyond the assumed distribution limit of the species in the Northwest Atlantic. A rapid return to the Scotian Shelf or Gulf of Maine was observed from several whales after incursions in southern waters, suggesting that fin whales in the Northwest Atlantic may not have a common winter destination that fits the definition of a breeding ground. Area-restricted search (ARS) behavior dominated fin whale activities during summer (92%) and fall (72%), with persistence into the winter (56%); ARS occurred at multiple locations in the GSL, Scotian Shelf and Shelf edge, and near seamounts of the North Atlantic, having characteristics consistent with foraging areas.


Assuntos
Migração Animal , Baleia Comum , Estações do Ano , Animais , Migração Animal/fisiologia , Baleia Comum/fisiologia , Oceano Atlântico , Canadá
2.
Science ; 381(6661): 990-995, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37651509

RESUMO

Phylogeny-based estimates suggesting a low germline mutation rate (µ) in baleen whales have influenced research ranging from assessments of whaling impacts to evolutionary cancer biology. We estimated µ directly from pedigrees in four baleen whale species for both the mitochondrial control region and nuclear genome. The results suggest values higher than those obtained through phylogeny-based estimates and similar to pedigree-based values for primates and toothed whales. Applying our estimate of µ reduces previous genetic-based estimates of preexploitation whale abundance by 86% and suggests that µ cannot explain low cancer rates in gigantic mammals. Our study shows that it is feasible to estimate µ directly from pedigrees in natural populations, with wide-ranging implications for ecological and evolutionary research.


Assuntos
Taxa de Mutação , Baleias , Animais , Linhagem , Baleias/genética
3.
Glob Chang Biol ; 28(8): 2657-2677, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35106859

RESUMO

Global warming is affecting the population dynamics and trophic interactions across a wide range of ecosystems and habitats. Translating these real-time effects into their long-term consequences remains a challenge. The rapid and extreme warming period that occurred after the Last Glacial Maximum (LGM) during the Pleistocene-Holocene transition (7-12 thousand years ago) provides an opportunity to gain insights into the long-term responses of natural populations to periods with global warming. The effects of this post-LGM warming period have been assessed in many terrestrial taxa, whereas insights into the impacts of rapid global warming on marine taxa remain limited, especially for megafauna. In order to understand how large-scale climate fluctuations during the post-LGM affected baleen whales and their prey, we conducted an extensive, large-scale analysis of the long-term effects of the post-LGM warming on abundance and inter-ocean connectivity in eight baleen whale and seven prey (fish and invertebrates) species across the Southern and the North Atlantic Ocean; two ocean basins that differ in key oceanographic features. The analysis was based upon 7032 mitochondrial DNA sequences as well as genome-wide DNA sequence variation in 100 individuals. The estimated temporal changes in genetic diversity during the last 30,000 years indicated that most baleen whale populations underwent post-LGM expansions in both ocean basins. The increase in baleen whale abundance during the Holocene was associated with simultaneous changes in their prey and climate. Highly correlated, synchronized and exponential increases in abundance in both baleen whales and their prey in the Southern Ocean were indicative of a dramatic increase in ocean productivity. In contrast, the demographic fluctuations observed in baleen whales and their prey in the North Atlantic Ocean were subtle, varying across taxa and time. Perhaps most important was the observation that the ocean-wide expansions and decreases in abundance that were initiated by the post-LGM global warming, continued for millennia after global temperatures stabilized, reflecting persistent, long-lasting impacts of global warming on marine fauna.


Assuntos
Ecossistema , Aquecimento Global , Animais , Oceano Atlântico , Dinâmica Populacional , Baleias/fisiologia
4.
Glob Chang Biol ; 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33368899

RESUMO

Climate change has resulted in physical and biological changes in the world's oceans. How the effects of these changes are buffered by top predator populations, and therefore how much plasticity lies at the highest trophic levels, are largely unknown. Here endocrine profiling, longitudinal observations of known individuals over 15 years between 2004 and 2018, and environmental data are combined to examine how the reproductive success of a top marine predator is being affected by ecosystem change. The Gulf of St. Lawrence, Canada, is a major summer feeding ground for humpback whales (Megaptera novaeangliae) in the North Atlantic. Blubber biopsy samples (n = 185) of female humpback whales were used to investigate variation in pregnancy rates through the quantification of progesterone. Annual pregnancy rates showed considerable variability, with no overall change detected over the study. However, a total of 457 photo-identified adult female sightings records with/without calves were collated, and showed that annual calving rates declined significantly. The probability of observing cow-calf pairs was related to favourable environmental conditions in the previous year; measured by herring spawning stock biomass, Calanus spp. abundance, overall copepod abundance and phytoplankton bloom magnitude. Approximately 39% of identified pregnancies were unsuccessful over the 15 years, and the average annual pregnancy rate was higher than the average annual calving rate at ~37% and ~23% respectively. Together, these data suggest that the declines in reproductive success could be, at least in part, the result of females being unable to accumulate the energy reserves necessary to maintain pregnancy and/or meet the energetic demands of lactation in years of poorer prey availability rather than solely an inability to become pregnant. The decline in calving rates over a period of major environmental variability may suggest that this population has limited resilience to such ecosystem change.

5.
J Pediatr ; 224: 87-93.e1, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32417086

RESUMO

OBJECTIVE: To assess the efficacy of mindfulness-based cognitive therapy delivered onsite during work hours in reducing stress and improving well-being in an interdisciplinary chronic care health care team. STUDY DESIGN: A longitudinal, mixed methods, observational pilot study using a survey created from validated assessment tools to measure effectiveness of training. Surveys were completed before training, and 1 and 15 months after training. Twenty-four professionals in the cystic fibrosis Centers at Cincinnati Children's Hospital and the University of Cincinnati participated in 6 mindfulness-based cognitive therapy training sessions. Sessions incorporated mindfulness, cognitive therapy, and experiential exercises for processing feelings related to stress and burnout. RESULTS: The presurvey and 1-month postsurvey responses revealed statistically significant improvements for empathy, perceived stress, depersonalization, anxiety, perspective taking, resilience, and negative affect. Sustained effects were seen at 15 months for empathy, perspective taking, and depressive symptoms. The 1-month post-training surveys reported a quarter of respondents (25%) practiced skills at least 5 times in between sessions; at 15 months, 35% reported practicing at the same frequency. Participants reported using mindfulness skills for personal stressful events (74%), work-related general stress (65%), patient-related stress (30%), sleep or general relaxation (22%), and wellness (13%). CONCLUSIONS: Group mindfulness-based cognitive therapy training was feasible and effective in decreasing stress for interdisciplinary cystic fibrosis care team members who elected to participate. Further investigation is needed to determine optimal dose of training, durability of perceived benefits, and generalizability to health care professionals working with other chronic disorders.


Assuntos
Esgotamento Profissional/prevenção & controle , Pessoal de Saúde/educação , Atenção Plena/educação , Esgotamento Profissional/diagnóstico , Doença Crônica/psicologia , Doença Crônica/terapia , Pessoal de Saúde/psicologia , Humanos , Estudos Longitudinais , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa , Inquéritos e Questionários
6.
Early Interv Psychiatry ; 14(2): 211-219, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31264800

RESUMO

AIM: Previous studies suggest that Mindfulness-Based Cognitive Therapy for Children (MBCT-C) is feasible and may improve anxiety and emotion regulation in youth with anxiety disorders at-risk for bipolar disorder. However, controlled studies are warranted to replicate and extend these findings. METHODS: In the current study, 24 youth with anxiety disorders who have at least one parent with bipolar disorder participated in a MBCT-C treatment period (n = 24; Mage = 13.6, 75% girls, 79% White) with a subset also participating in a prior psychoeducation waitlist control period (n = 19 Mage = 13.8, 68% girls, 84% White). Participants in both the waitlist and MBCT-C periods completed independently-rated symptom scales at each time point. Participants in the waitlist period received educational materials 12 weeks prior to the beginning of MBCT-C. RESULTS: There were significantly greater improvements in overall clinical severity in the MBCT-C period compared to the waitlist period, but not in clinician- and child-rated anxiety, emotion regulation or mindfulness. However, increases in mindfulness were associated with improvements in anxiety and emotion regulation in the MBCT-C period, but not the waitlist period. CONCLUSIONS: Findings suggest that MBCT-C may be effective for improving overall clinical severity in youth with anxiety disorders who are at-risk for bipolar disorder. However, waitlist controlled designs may inflate effect sizes so interpret with caution. Larger studies utilizing prospective randomized controlled designs are warranted.


Assuntos
Transtornos de Ansiedade/terapia , Filho de Pais com Deficiência/psicologia , Terapia Cognitivo-Comportamental/métodos , Atenção Plena/métodos , Adolescente , Transtorno Bipolar , Feminino , Humanos , Masculino , Projetos Piloto , Sintomas Prodrômicos , Estudos Prospectivos , Resultado do Tratamento , Listas de Espera
7.
Ecol Evol ; 9(7): 4231-4244, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31016001

RESUMO

Estimates of abundance and survivorship provide quantifiable measures to monitor populations and to define and understand their conservation status. This study investigated changes in abundance and survival rates of fin whales (Balaenoptera physalus) in the northern Gulf of St. Lawrence in the context of anthropogenic pressures and changing environmental conditions. A long-term data set, consisting of 35 years of photo-identification surveys and comprising more than 5,000 identifications of 507 individuals, formed the basis of this mark-recapture study. Based on model selection using corrected Akaike Information Criterion, the most parsimonious Cormack-Jolly-Seber model included a linear temporal trend in noncalf apparent survival rates with a sharp decline in the last 5 years of the study and a median survival rate of 0.946 (95% confidence interval (CI) 0.910-0.967). To account for capture heterogeneity due to divergent patterns of site fidelity, agglomerative hierarchical cluster analysis was employed to categorize individuals based on their annual and survey site fidelity indices. However, the negative trend in survivorship remained and was corroborated by a significant decline in the estimated super-population size from 335 (95% CI 321-348) individuals in 2004-2010 to 291 (95% CI 270-312) individuals in 2010-2016. Concurrently, a negative trend was estimated in recruitment to the population, supported by a sharp decrease in the number of observed calves. Ship strikes and changes in prey availability are potential drivers of the observed decline in fin whale abundance. The combination of clustering methods with mark-recapture represents a flexible way to investigate the effects of site fidelity on demographic variables and is broadly applicable to other individual-based studies.

8.
Mol Phylogenet Evol ; 135: 86-97, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30771513

RESUMO

The advent of massive parallel sequencing technologies has resulted in an increase of studies based upon complete mitochondrial genome DNA sequences that revisit the taxonomic status within and among species. Spatially distinct monophyly in such mitogenomic genealogies, i.e., the sharing of a recent common ancestor among con-specific samples collected in the same region has been viewed as evidence for subspecies. Several recent studies in cetaceans have employed this criterion to suggest subsequent intraspecific taxonomic revisions. We reason that employing intra-specific, spatially distinct monophyly at non-recombining, clonally inherited genomes is an unsatisfactory criterion for defining subspecies based upon theoretical (genetic drift) and practical (sampling effort) arguments. This point was illustrated by a re-analysis of a global mitogenomic assessment of fin whales, Balaenoptera physalus spp., published by Archer et al. (2013), which proposed to further subdivide the Northern Hemisphere fin whale subspecies, B. p. physalus. The proposed revision was based upon the detection of spatially distinct monophyly among North Atlantic and North Pacific fin whales in a genealogy based upon complete mitochondrial genome DNA sequences. The extended analysis conducted in this study (1676 mitochondrial control region, 162 complete mitochondrial genome DNA sequences and 20 microsatellite loci genotyped in 380 samples) revealed that the apparent monophyly among North Atlantic fin whales reported by Archer et al. (2013) to be due to low sample sizes. In conclusion, defining sub-species from monophyly (i.e., the absence of para- or polyphyly) can lead to erroneous conclusions due to relatively "trivial" aspects, such as sampling. Basic population genetic processes (i.e., genetic drift and migration) also affect the time to the most recent common ancestor and hence the probability that individuals in a sample are monophyletic.


Assuntos
Baleia Comum/classificação , Baleia Comum/genética , Genoma Mitocondrial , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , DNA Mitocondrial/genética , Variação Genética , Genótipo , Geografia , Repetições de Microssatélites/genética
9.
Mindfulness (N Y) ; 8(6): 1522-1531, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29335671

RESUMO

Hospital employees may experience occupational stress and burnout, which negatively impact quality of life and job performance. Evidence-based interventions implemented within the hospital setting are needed to promote employees' well-being. We offered a 4-week Mindfulness-Based Cognitive Therapy group program for hospital employees, and used a mixed-methods practice-based research approach to explore feasibility, acceptability, and effects on stress and burnout. Participants were 65 hospital employees (Mage = 44.06; 85% white) who participated between September 2015 and January 2016. Participants completed validated measures of stress and burnout before and after the program, and answered open-ended satisfaction questions after the program. Groups consistently enrolled at least 10 participants, but attendance rates declined across sessions (76% at session 2 vs. 54% at session 4) due primarily to work-related scheduling conflicts. The program content was acceptable as evidenced by high perceived value (M = 9.18 out of 10), homework compliance (51% practicing at least 3 times/week), and qualitative requests for program expansion. There were large, statistically significant decreases in stress (ΔM = 2.1, p < .001, d = .85) and medium decreases in burnout (ΔM = .46, p = .01, d = .57), which were supported by qualitative themes of improved self-regulation and mindfulness skills, stress reduction, emotional well-being, and improved work productivity and patient care skills. Findings suggest that 4-week MBCT is acceptable and useful for hospital employees, though research is needed to identify alternate delivery methods or strategies to enhance session attendance.

10.
J Child Adolesc Psychopharmacol ; 26(4): 372-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26783833

RESUMO

OBJECTIVE: We sought to evaluate the neurophysiology of mindfulness-based cognitive therapy for children (MBCT-C) in youth with generalized, social, and/or separation anxiety disorder who were at risk for developing bipolar disorder. METHODS: Nine youth (mean age: 13 ± 2 years) with a generalized, social, and/or separation anxiety disorder and a parent with bipolar disorder completed functional magnetic resonance imaging (fMRI) while performing a continuous processing task with emotional and neutral distractors (CPT-END) prior to and following 12 weeks of MBCT-C. RESULTS: MBCT-C was associated with increases in activation of the bilateral insula, lentiform nucleus, and thalamus, as well as the left anterior cingulate while viewing emotional stimuli during the CPT-END, and decreases in anxiety were correlated with change in activation in the bilateral insula and anterior cingulate during the viewing of emotional stimuli (p < 0.05, uncorrected; p < 0.005 corrected; cluster size, 37 voxels). CONCLUSIONS: MBCT-C treatment in anxious youth with a familial history of bipolar disorder is associated with increased activation of brain structures that subserve interoception and the processing of internal stimuli-functions that are ostensibly improved by this treatment.


Assuntos
Transtornos de Ansiedade/terapia , Transtorno Bipolar/prevenção & controle , Terapia Cognitivo-Comportamental/métodos , Atenção Plena/métodos , Adolescente , Transtornos de Ansiedade/psicologia , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Fatores de Risco , Resultado do Tratamento
11.
Early Interv Psychiatry ; 10(5): 426-34, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-25582800

RESUMO

AIM: Children and adolescents with bipolar parents have an elevated risk for anxiety disorders. However, antidepressant medications commonly used to treat symptoms of anxiety may accelerate the onset of mania in these already at-risk youth. Therefore, studies evaluating innovative non-pharmacologic treatments for anxiety in this population are urgently needed. METHODS: Subjects participated in 12 weekly sessions of mindfulness-based cognitive therapy for children (MBCT-C), a manualized group psychotherapeutic intervention utilizing cognitive behavioural principles and mindfulness exercises to increase regulation of attention and non-judgmental acceptance of present moment thoughts, emotions and experiences. Independent raters administered symptoms rating scales prior to each treatment session. Spearman correlations and paired-samples signed rank tests were used to examine outcomes. After-intervention surveys and session transcripts were reviewed to assess feasibility and acceptability of the intervention. RESULTS: Participants included 10 youth (meanage = 13.2; 80% girls; 40% biracial) with generalized, social and/or separation anxiety disorders, and a parent with bipolar disorder. Clinician-rated anxiety was significantly reduced after intervention (meanbefore = 11.1; meanafter = 4.3; P < 0.01), as well as youth-rated trait anxiety (P = 0.03). Parent-rated emotion regulation significantly increased from before to after intervention (P = 0.05). Increases in mindfulness were associated with decreases in anxiety (P = 0.03). Finally, children and parents/guardians reported high levels of feasibility, acceptability and usefulness of the intervention. CONCLUSION: Findings support the feasibility, acceptability and preliminary efficacy of MBCT-C for treating anxiety in youth at risk for bipolar disorder. Future controlled and larger studies are needed to confirm these preliminary findings.


Assuntos
Transtornos de Ansiedade/terapia , Terapia Cognitivo-Comportamental/métodos , Atenção Plena , Adolescente , Transtorno Bipolar/psicologia , Criança , Feminino , Humanos , Masculino , Pais/psicologia , Projetos Piloto , Psicoterapia de Grupo
12.
PLoS One ; 10(3): e0121374, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785462

RESUMO

Global warming poses particular challenges to migratory species, which face changes to the multiple environments occupied during migration. For many species, the timing of migration between summer and winter grounds and also within-season movements are crucial to maximise exploitation of temporarily abundant prey resources in feeding areas, themselves adapting to the warming planet. We investigated the temporal variation in the occurrence of fin (Balaenoptera physalus) and humpback whales (Megaptera novaeangliae) in a North Atlantic summer feeding ground, the Gulf of St. Lawrence (Canada), from 1984 to 2010 using a long-term study of individually identifiable animals. These two sympatric species both shifted their date of arrival at a previously undocumented rate of more than 1 day per year earlier over the study period thus maintaining the approximate 2-week difference in arrival of the two species and enabling the maintenance of temporal niche separation. However, the departure date of both species also shifted earlier but at different rates resulting in increasing temporal overlap over the study period indicating that this separation may be starting to erode. Our analysis revealed that the trend in arrival was strongly related to earlier ice break-up and rising sea surface temperature, likely triggering earlier primary production. The observed changes in phenology in response to ocean warming are a remarkable example of phenotypic plasticity and may partly explain how baleen whales were able to survive a number of changes in climate over the last several million years. However, it is questionable whether the observed rate of change in timing can be maintained. Substantial modification to the distribution or annual life cycle of these species might be required to keep up with the ongoing warming of the oceans.


Assuntos
Adaptação Fisiológica , Migração Animal , Jubarte/fisiologia , Movimento , Oceanos e Mares , Estações do Ano , Temperatura , Animais , Aquecimento Global , Inquéritos e Questionários
13.
Curr Psychiatry Rep ; 15(9): 391, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23943471

RESUMO

Integrative medicine (IntM) is a growing medical trend combining conventional medical approaches with evidence-based complementary therapies to promote well-being. Over half of individuals with depression use some form of IntM for symptom management. The purpose of the current study was to critically review the scientific evidence for IntM techniques in treating adult unipolar depression. We examined randomized controlled trials, systematic reviews, and meta-analyses published in the last one to three years using PsychINFO, PubMed, and Cochrane Library databases. The strongest evidence currently exists for mindfulness-based interventions and St. John's Wort (SJW) as monotherapies, and there is relatively strong evidence to support the use of omega-3 fatty acids and exercise as adjunct therapies. However, there remains an overall lack of methodologically rigorous research to support the efficacy of many other IntM techniques. Providers should be aware that many patients use IntM techniques for depression treatment and inquire regularly about such use.


Assuntos
Terapias Complementares , Transtorno Depressivo/terapia , Medicina Integrativa/métodos , Medicina Baseada em Evidências , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Mar Environ Res ; 57(4): 245-60, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14749058

RESUMO

Biopsy samples of blubber from adult male and female blue whales, and from female and young-of-the-year humpback whales were collected during the summers of 1992-1999 in the Gulf of St. Lawrence, Canada. In blue whales, concentrations of 25 PCB congeners, DDT and metabolites and several other organochlorine compounds were present at higher concentrations in the blubber of males relative to females; reflecting maternal transfer of these persistent contaminants from females into young. Sex-related differences in concentrations were not observed with less persistent contaminants, such as HCHs. In humpback whale samples, there were no significant differences in the concentrations of PCBs and organochlorine compounds in the blubber of females and calves. These data indicate that calves quickly bioaccumulate contaminants by transplacental and lactational routes to concentrations that are in equilibrium with females. In comparisons between contaminant concentrations and patterns in the blubber of female blue and humpback whales, there were no significant differences in concentrations, but the proportions of some PCB congeners, HCH isomers, and DDT and its metabolites were different in the two baleen whale species. These may reflect differences in the diet of the two species, since fish comprise a large part of the diet of humpback whales and blue whales feed exclusively on euphausiid crustaceans (i.e. krill).


Assuntos
Tecido Adiposo/química , DDT/análise , Bifenilos Policlorados/análise , Baleias , Análise de Variância , Animais , Oceano Atlântico , Canadá , Cromatografia Gasosa , DDT/farmacocinética , Feminino , Masculino , Troca Materno-Fetal , Bifenilos Policlorados/farmacocinética , Gravidez , Análise de Componente Principal , Especificidade da Espécie
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