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1.
Ecol Lett ; 27(1): e14335, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37972585

RESUMO

Foraging decisions shape the structure of food webs. Therefore, a behavioural shift in a single species can potentially modify resource-flow dynamics of entire ecosystems. To examine this, we conducted a field experiment to assess foraging niche dynamics of semi-arboreal brown anole lizards in the presence/absence of predatory ground-dwelling curly-tailed lizards in a replicated set of island ecosystems. One year after experimental translocation, brown anoles exposed to these predators had drastically increased perch height and reduced consumption of marine-derived food resources. This foraging niche shift altered marine-to-terrestrial resource-flow dynamics and persisted in the diets of the first-generation offspring. Furthermore, female lizards that displayed more risk-taking behaviours consumed more marine prey on islands with predators present. Our results show how predator-driven rapid behavioural shifts can alter food-web connectivity between oceanic and terrestrial ecosystems and underscore the importance of studying behaviour-mediated niche shifts to understand ecosystem functioning in rapidly changing environments.


Assuntos
Ecossistema , Lagartos , Animais , Feminino , Cadeia Alimentar , Comportamento Predatório
2.
Br J Psychiatry ; 219(5): 578-587, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33533706

RESUMO

BACKGROUND: In most trials and systematic reviews that evaluate exercise-based interventions in reducing depressive symptoms, it is difficult to separate treatment from prevention. AIMS: To evaluate the effectiveness of exercise-based interventions in reducing depressive symptoms in people without clinical depression. METHOD: We searched PubMed, PsycINFO, Embase, WOS, SPORTDiscus, CENTRAL, OpenGrey and other sources up to 25 May 2020. We selected randomised controlled trials (RCTs) that compared exclusively exercise-based interventions with control groups, enrolling participants without clinical depression, as measured using validated instruments, and whose outcome was reduction of depressive symptoms and/or incidence of new cases of people with depression. Pooled standardised mean differences (SMDs) were calculated using random-effect models (registration at PROSPERO: CRD42017055726). RESULTS: A total of 14 RCTs (18 comparisons) evaluated 1737 adults without clinical depression from eight countries and four continents. The pooled SMD was -0.34 (95% CI -0.51 to -0.17; P < 0.001) and sensitivity analyses confirmed the robustness of this result. We found no statistical evidence of publication bias and heterogeneity was moderate (I2 = 54%; 95% CI 22-73%). Only two RCTs had an overall low risk of bias and three had long-term follow-up. Multivariate meta-regression found that a larger sample size, country (Asia) and selective prevention (i.e. people exposed to risk factors for depression) were associated with lower effectiveness, although only sample size remained significant when adjustment for multiple tests was considered. According to the Grading of Recommendations Assessment, Development and Evaluation tool, the quality of evidence was low. CONCLUSIONS: Exercise-based interventions have a small effect on the reduction of depressive symptoms in people without clinical depression. It could be an alternative to or complement psychological programmes, although further higher-quality trials with larger samples and long-term follow-up are needed.


Assuntos
Depressão , Transtorno Depressivo Maior , Adulto , Depressão/diagnóstico , Depressão/prevenção & controle , Transtorno Depressivo Maior/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Conserv Biol ; 33(2): 413-422, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30346052

RESUMO

Wind energy development is the most recent of many pressures on upland bird communities and their habitats. Studies of birds in relation to wind energy development have focused on effects of direct mortality, but the importance of indirect effects (e.g., displacement, habitat loss) on avian community diversity and stability is increasingly being recognized. We used a control-impact study in combination with a gradient design to assess the effects of wind farms on upland bird densities and on bird species grouped by habitat association (forest and open-habitat species). We conducted 506 point count surveys at 12 wind-farm and 12 control sites in Ireland during 2 breeding seasons (2012 and 2013). Total bird densities were lower at wind farms than at control sites, and the greatest differences occurred close to turbines. Densities of forest species were significantly lower within 100 m of turbines than at greater distances, and this difference was mediated by habitat modifications associated with wind-farm development. In particular, reductions in forest cover adjacent to turbines was linked to the observed decrease in densities of forest species. Open-habitat species' densities were lower at wind farms but were not related to distance from turbines and were negatively related to size of the wind farm. This suggests that, for these species, wind-farm effects may occur at a landscape scale. Our findings indicate that the scale and intensity of the displacement effects of wind farms on upland birds depends on bird species' habitat associations and that the observed effects are mediated by changes in land use associated with wind-farm construction. This highlights the importance of construction effects and siting of turbines, tracks, and other infrastructure in understanding the impacts of wind farms on biodiversity.


Efectos del Desarrollo de la Energía Eólica y los Cambios Asociados al Uso de Suelo sobre las Densidades de Aves en Tierras Altas Resumen El desarrollo de la energía eólica es la más reciente de muchas presiones ejercidas sobre las comunidades de aves de tierras altas y sus hábitats. Los estudios sobre aves en relación con el desarrollo de la energía eólica se han enfocado en los efectos de la mortalidad directa, pero la importancia de los efectos indirectos (p. ej.: desplazamiento, pérdida de hábitat) sobre la diversidad y estabilidad de las comunidades aviares cada vez se reconoce más. Usamos un estudio de control-impacto combinado con un diseño de gradiente para evaluar los efectos de los campos eólicos sobre las densidades de aves de tierras altas y sobre las especies de aves agrupadas por asociación de hábitat (especies de bosque y de hábitat abierto). Realizamos 506 censos de conteo por puntos en 12 sitios de campos eólicos y 12 sitios control en Irlanda durante dos temporadas de reproducción (2012 y 2013). Las densidades de aves totales fueron más bajas en los campos eólicos que en los sitios control, con las diferencias más importantes ocurriendo cerca de las turbinas. Las densidades de las especies de bosque fueron significativamente más bajas a 100 m de las turbinas que a distancias mayores y esta diferencia estuvo mediada por modificaciones asociadas con el desarrollo de campos eólicos. De manera particular, las reducciones en la cobertura de bosque adyacente a las turbinas estuvieron vinculadas con la disminución observada en las densidades de las especies de bosque. Las densidades de las especies de hábitat abierto fueron más bajas en los campos eólicos pero no estuvieron relacionadas con la distancia a las turbinas y tuvieron una relación negativa con el tamaño del campo eólico. Lo anterior sugiere que, para estas especies, los efectos del campo eólico pueden ocurrir a la escala de paisaje. Nuestros hallazgos indican que la escala y la intensidad de los efectos de desplazamiento de los campos eólicos sobre las aves de tierras altas dependen de las asociaciones de hábitat de las especies de aves y que los efectos observados están mediados por cambios en el uso de suelo asociados con la construcción de campos eólicos. Esto remarca la importancia de los efectos de construcción y el sitiado de las turbinas, pistas y demás infraestructura en el entendimiento de los impactos que tienen los campos eólicos sobre la biodiversidad.


Assuntos
Conservação dos Recursos Naturais , Fontes Geradoras de Energia , Animais , Aves , Ecossistema , Vento
4.
Ecology ; 97(2): 406-16, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27145615

RESUMO

Understanding how density dependence modifies demographic parameters in long-lived vertebrates is a challenge for ecologists. Two alternative hypotheses have been used to explain the mechanisms behind density-dependent effects on breeding output: habitat heterogeneity and individual adjustment (also known as interference competition). A number of studies have highlighted the importance of habitat heterogeneity in density dependence in territorial species, but less information exists on demographic processes in colonial species. For these, we expect density-dependent mechanisms to operate at two spatial scales: colony and breeding unit. In this study, we used long-term data from a recovering population of Cinereous Vultures (Aegypius monachus) in southern Spain. We analyzed a long-term data set with information on 2162 breeding attempts at four colonies over a nine-year period (2002-2010) to evaluate environmental and population parameters influencing breeding output. Our results suggest that breeding productivity is subject to density-dependent processes at the colony and the nest site scale and is best explained by interference competition. Factors intrinsic to each colony, as well as environmental constraints linked to physiography and human presence, also play a role in regulatory processes. We detected the existence of a trade-off between the disadvantages of nesting too close to conspecifics and the benefits of coloniality. These could be mediated by the agonistic interactions between breeding pairs and the benefits derived from social sharing of information by breeding individuals. We propose that this trade-off may play a role in defining colony structure and may hold true for other colonial breeding bird species. Our findings also have important management implications for the conservation of this threatened species.


Assuntos
Falconiformes/fisiologia , Reprodução/fisiologia , Animais , Conservação dos Recursos Naturais , Ecossistema , Comportamento de Nidação , Densidade Demográfica , Espanha , Fatores de Tempo
5.
Int J Clin Health Psychol ; 24(2): 100450, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525016

RESUMO

Objective: To examine the associations between muscular strength and mental health. Design: We used baseline data of 91 cognitively healthy older adults (71.69 ± 3.91 years old, 57 % women) participating in the AGUEDA randomized controlled trial. Methods: Muscular strength was assessed using both objective (i.e., handgrip strength, biceps curl, squats, and isokinetic test) and perceived (i.e., International Fitness Scale) indicators. Psychological ill-being indicators: anxiety, depression, stress, and loneliness; and psychological well-being indicators: satisfaction with life, self-esteem, and emotional well-being) were assessed using a set of valid and reliable self-reported questionnaires. Linear regression analyses were performed adjusting for sex, age, years of education, body mass index , alcohol, diet, and smoking (model 1), and additionally by cardiorespiratory fitness (model 2). Results: Elbow extension was positively associated with stress in model 1 (ß = 0.252, 95 % Confidence Interval [95 % CI] = 0.007 to 0.497, p = 0.044), and even after further adjustment for cardiorespiratory fitness (ß = 0.282, 95 % CI = 0.032 to 0.532, p = 0.028). Perceived strength was negatively associated with depressive symptoms in model 1 (ß = -0.271, 95 % CI = -0.491 to -0.049, p = 0.017) and model 2 reported associations tending towards significant (ß = -0.220, 95 % CI = -0.445 to 0.005, p = 0.055). Handgrip strength was positively associated with self-esteem in model 1 (ß = 0.558, 95 % CI = 0.168 to 0.949, p = 0.006) and model 2 (ß = 0.546, 95 % CI = 0.135 to 0.956, p = 0.010). No further associations were found among other muscular strength and mental health variables. Conclusion: Handgrip had a moderate association with self-esteem and there was a small association between perceived strength with depressive symptoms and elbow extension with stress. No other associations were observed between muscular strength and mental health outcomes in cognitively normal older adults.

6.
Front Hum Neurosci ; 17: 1168549, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284481

RESUMO

Alzheimer's disease is currently the leading cause of dementia and one of the most expensive, lethal and severe diseases worldwide. Age-related decline in executive function is widespread and plays a key role in subsequent dementia risk. Physical exercise has been proposed as one of the leading non-pharmaceutical approaches to improve executive function and ameliorate cognitive decline. This single-site, two-arm, single-blinded, randomized controlled trial (RCT) will include 90 cognitively normal older adults, aged 65-80 years old. Participants will be randomized to a 24-week resistance exercise program (3 sessions/week, 60 min/session, n = 45), or a wait-list control group (n = 45) which will be asked to maintain their usual lifestyle. All study outcomes will be assessed at baseline and at 24-weeks after the exercise program, with a subset of selected outcomes assessed at 12-weeks. The primary outcome will be indicated by the change in an executive function composite score assessed with a comprehensive neuropsychological battery and the National Institutes of Health Toolbox Cognition Battery. Secondary outcomes will include changes in brain structure and function and amyloid deposition, other cognitive outcomes, and changes in molecular biomarkers assessed in blood, saliva, and fecal samples, physical function, muscular strength, body composition, mental health, and psychosocial parameters. We expect that the resistance exercise program will have positive effects on executive function and related brain structure and function, and will help to understand the molecular, structural, functional, and psychosocial mechanisms involved.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35162835

RESUMO

The aim of this study was to evaluate the effectiveness of physical activity in the primary prevention of anxiety. A systematic review of randomized controlled trials (RCTs) was performed. RCTs were searched in seven electronic databases. We included RCTs that assessed either the incidence of anxiety or the reduction of anxiety symptoms which excluded participants with baseline anxiety. Measurements were required to have been made using validated instruments. Objective or subjective (with validated questionnaires) verification of the performance of physical activity was required. Three reviewers carried out the search, selection, data extraction, and risk assessment of Cochrane Collaboration's tool simultaneously and independently, reaching an agreement in their discrepancies by consensus. In addition, a meta-analysis of fixed-effects model was carried out. Three RCTs met inclusion criteria, comprising 350 patients from 3 different countries. A meta-analysis was performed using five comparisons extracted from the selected studies, and the pooled standardized mean difference (SMD) was -0.18 (95% CI: -0.44; 0.07), p = 0.158. The heterogeneity was irrelevant, I2 = 17.7% (p = 0.30). There is no evidence that anxiety can be prevented through physical activity, although the quality of evidence was very low.


Assuntos
Transtornos de Ansiedade , Ansiedade , Ansiedade/prevenção & controle , Exercício Físico , Humanos , Prevenção Primária , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Sci Total Environ ; 737: 140238, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783846

RESUMO

Wind energy is a key component of climate action strategies aimed at reducing our dependence on fossil fuels. Despite providing environmental benefits, there are increasing concerns surrounding the impact of wind farms on wildlife, with research indicating that effects on wildlife can be highly variable between species, regions, and sites. In light of this variability and the accelerating growth of the wind energy sector globally, a comprehensive understanding of wind farm effects on wildlife and ease of access to this knowledge are pivotal to inform best practice if wind energy is to become a truly sustainable source of energy. This review evaluates interactions between a globally distributed bird genus (harriers, Circus sp.) and wind farms to assess broader patterns in wildlife-wind energy knowledge accessibility and bias. A systematic review of grey and peer-reviewed literature across two multidisciplinary and two field-specific databases in two languages (English and Spanish) yielded 235 relevant sources, covering 12 harrier species and 31 countries. Findings indicate that harriers are considered to have high sensitivity to wind farms, with greatest impacts expected from habitat effects rather than from turbine collisions. In the broader wildlife-wind energy context, this study underscores (i) the predominance of grey literature and of sources solely documenting species-wind farm overlaps; (ii) limitations in grey literature availability and peer-reviewed publication accessibility; (iii) lack of standardized research and monitoring practices; and (iv) evidence of language, taxonomic, and geographic bias in literature sources. Overall, findings demonstrate that limited accessibility to wildlife-wind energy knowledge risks widening the research-implementation gap. Widespread implementation of open practices that allow researchers and practitioners to build on existing knowledge (e.g. national and international online repositories and databases, knowledge sharing and collaborative initiatives, open access publications) is crucial if ongoing wind energy development efforts are to be successfully aligned with conservation priorities.


Assuntos
Fontes Geradoras de Energia , Vento , Animais , Animais Selvagens , Aves , Ecossistema
9.
Conserv Lett ; 13(1): e12678, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194654

RESUMO

In urbanized societies that are increasingly disconnected from nature, communicating ecological and species awareness is crucial to revert the global environmental crisis. However, our understanding of the effectiveness of this process is limited. We present a framework for describing how such awareness may be transferred and test it on the popular BBC show Planet Earth 2 by analyzing Twitter and Wikipedia big data activity. Despite lacking explicit conservation themes, this show generated species awareness, stimulating audience engagement for information at magnitudes comparable to those achieved by other conservation-focused campaigns. Results suggest that natural history films can provide vicarious connections to nature and can generate durable shifts in audience awareness beyond the broadcast of the show-key factors for changing environmental attitudes. More broadly, this study underscores how open-source big data analysis can inform effective dissemination of ecological awareness and provides a framework for future research for investigating behavioral change.

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