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1.
Nature ; 572(7770): 461-466, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31340216

RESUMO

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.


Assuntos
Migração Animal , Pesqueiros/estatística & dados numéricos , Mapeamento Geográfico , Oceanos e Mares , Tubarões/fisiologia , Análise Espaço-Temporal , Animais , Densidade Demográfica , Medição de Risco , Tubarões/classificação , Navios , Fatores de Tempo
2.
J Fish Biol ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533638

RESUMO

Migration is a critical aspect of ocean ecosystems, and understanding this phenomenon answers ecological and management questions. Given the difficulty in tracking ocean animals across large distances, the extent to which different ray species perform long-distance movements, such as migrations, remains unknown. This study used passive acoustic telemetry to track the movements of endemic diamond Gymnura natalensis and critically endangered duckbill Aetomylaeus bovinus rays along the South African coastline using a collaborative nationwide network of coastal acoustic receivers for up to 7 years. Duckbill rays were detected significantly more frequently than diamond rays, but both species moved between the south and east coasts of South Africa (traveling up to 1167 km). Tagged individuals were detected significantly more often in their tagging locations during summer months but traveled significantly further distances during winter months. Furthermore, movement models fitted to individual duckbill rays' annual net-squared displacement identified most individual annual movements as migratory. This evidence suggests that both diamond and duckbill rays make eastward winter migrations and return to specific areas along the coastline during the summer months. The exceptions to this were diamond rays tagged on the east coast that were not found to migrate seasonally, which supports previous research that there is intraspecific variability in migrations for ray species. These findings have implications for understanding ray migration not only on a global scale but also locally for spatial management interventions and population delineation.

3.
Oecologia ; 201(3): 673-688, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36930348

RESUMO

The coexistence of ecologically and morphologically similar species is often facilitated by the partitioning of ecological niches. While subordinate species can reduce competition with dominant competitors through spatial and/or trophic segregation, empirical support from wild settings, particularly those involving large-bodied taxa in marine ecosystems, are rare. Shark nursery areas provide an opportunity to investigate the mechanisms of coexistence. We used experimental and field studies of sympatric juvenile sharks (blacktip reef shark, Carcharhinus melanopterus; sicklefin lemon shark, Negaprion acutidens) to investigate how competitive ability influenced realized niches at St. Joseph Atoll, Seychelles. Captive trials revealed that sicklefin lemon sharks were dominant over blacktip reef sharks, consistently taking food rewards. In the field, blacktip reef sharks were captured over a broader area than sicklefin lemon sharks, but daily space use of actively tracked sharks showed a high degree of overlap across microhabitats. While stomach contents analysis revealed that blacktip reef shark diets included a broader range of prey items, stable isotope analysis demonstrated significantly higher mean δ13C values for sicklefin lemon sharks, suggesting diverging dietary preferences. Overall, our results matched theoretical predictions of subordinate competitors using a greater range of habitats and displaying broader feeding niches than competitively dominant species. While separating the realized and fundamental niche of marine predators is complicated, we provide evidence that resource partitioning is at least partially driven by interspecific competition.


Assuntos
Ecossistema , Tubarões , Animais , Estado Nutricional
4.
Zoo Biol ; 42(5): 625-631, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37186331

RESUMO

Movements of four adult giant trevally Caranx ignobilis were tracked using passive acoustic telemetry after being released from uShaka Sea World Aquarium in Durban, South Africa, where they had been kept on display for a period of 8 years. All four individuals were detected on a large network of deployed acoustic receivers for a minimum of 3 months to a maximum of over 6 years. Their movements were compared to 43 wild-caught and tagged C. ignobilis over a similar period and two individuals adopted movement behavior similar to that of their conspecifics, including repeated annual seasonal migrations to a known spawning aggregation site. This study shows that with good animal husbandry, indigenous fish kept in captivity can be released back into the wild and not only survive but adopt natural movement behavior and contribute to future generations of their species.

7.
Curr Treat Options Oncol ; 21(10): 83, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32789716

RESUMO

OPINION STATEMENT: As the world becomes more connected through online and offline social networking, there has been much discussion of how the rapid rise of social media could be used in ways that can be productive and instructive in various healthcare specialties, such as Cardiology and its subspecialty areas. In this review, the role of social media in the field of Cardio-Oncology is discussed. With an estimated 17 million cancer survivors in the USA in 2019 and 22 million estimated by 2030, more education and awareness are needed. Networking and collaboration are also needed to meet the needs of our patients and healthcare professionals in this emerging field bridging two disciplines. Cardiovascular disease is second only to recurrence of the primary cancer or diagnosis with a secondary malignancy, as a leading cause of death in cancer survivors. A majority of these survivors are anticipated to be on social media seeking information, support, and ideas for optimizing health. Healthcare professionals in Cardio-Oncology are also online for networking, education, scholarship, career development, and advocacy in this field. Here, we describe the utilization and potential impact of social media in Cardio-Oncology, with inclusion of various hashtags frequently used in the Cardio-Oncology Twitter community.


Assuntos
Sobreviventes de Câncer/psicologia , Doenças Cardiovasculares/terapia , Neoplasias/terapia , Mídias Sociais/estatística & dados numéricos , Doenças Cardiovasculares/complicações , Humanos , Neoplasias/complicações
8.
J Nerv Ment Dis ; 206(8): 606-613, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30020205

RESUMO

Cognitive remediation (CR) training improves cognition and functioning in patients with psychosis. To date, however, few studies have investigated CR from a subjective patient perspective. We recently conducted a randomized control trial demonstrating the effectiveness of a new, low therapist support, computer-based training program. This study aims to assess the service user experience of this program. Twenty CR completers with psychosis were interviewed using both rated and open-ended questions. Thematic analysis identified three broad themes: a) benefits of doing CR, b) costs of doing CR, and c) experience of doing CR. Positive experiences of therapy participation included improved cognition, improved positive self-regard, a development of life skills, and a transfer of benefits to everyday life. Negative experiences included therapy being difficult and tiring, leading to frustration and anxiety. These findings demonstrate the feasibility of low therapist support CR and point to variables that might impact therapy adherence.


Assuntos
Disfunção Cognitiva/terapia , Remediação Cognitiva/métodos , Transtornos Psicóticos/terapia , Terapia Assistida por Computador , Adulto , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Transtornos Psicóticos/psicologia , Resultado do Tratamento
9.
J Chem Phys ; 147(6): 061102, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28810794

RESUMO

In a recent set of articles [J. C. Araque et al., J. Phys. Chem. B 119(23), 7015-7029 (2015) and J. C. Araque et al., J. Chem. Phys. 144, 204504 (2016)], we proposed the idea that for small neutral and charged solutes dissolved in ionic liquids, deviation from simple hydrodynamic predictions in translational and rotational dynamics can be explained in terms of diffusion through nano-environments that are stiff (high electrostriction, charge density, and number density) and others that are soft (charge depleted). The current article takes a purely solvent-centric approach in trying to provide molecular detail and intuitive visual understanding of time-dependent local mobility focusing on the most common case of an ionic liquid with well defined polar and apolar nano-domains. We find that at intermediate time scales, apolar regions are fluid, whereas the charge network is much less mobile. Because apolar domains and cationic heads must diffuse as single species, at long time the difference in mobility also necessarily dissipates.

10.
J Chem Phys ; 144(20): 204504, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27250313

RESUMO

When solutes are small compared to the size of the ions in an ionic liquid, energetic heterogeneities associated with charge enhanced (stiff) and charge depleted (soft) nanoenvironments are sampled. In a recent article [J. C. Araque et al., J. Phys. Chem. B 119(23), 7015-7029 (2015)], we explored large deviations from Stokes-Einstein translational diffusion caused by such a heterogeneity. The current article is set to explore the effect of soft and stiff solvent environments (i.e., structure) on OH-bond rotations in the case of water and small alcohols in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (Im1,2 (+)NTf2 (-)). Is solute rotational dynamics heterogeneous? If so, are solute rotations and translations coupled in the sense that stiff and soft solvent environments hinder or speed up both types of dynamics? For the systems studied here, there appears to be a clear connection between translations, rotations, and stiff/soft solvent environments. We also discuss interesting asymmetries of the correlation between solutes with anions and cations.

11.
Ecology ; 95(6): 1591-603, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25039223

RESUMO

The emission of volatile monoterpenes from coniferous trees impacts the oxidative state of the troposphere and multi-trophic signaling between plants and animals. Previous laboratory studies have revealed that climate anomalies and herbivory alter the rate of tree monoterpene emissions. However, no studies to date have been conducted to test these relations in situ. We conducted a two-year field experiment at two semiarid sites dominated by pinyon pine (Pinus edulis) during outbreaks of a specialist herbivore, the southwestern tiger moth (Lophocampa ingens: Arctiidae). We discovered that during the early spring, when herbivory rates were highest, monoterpene emission rates were approximately two to six times higher from undamaged needles on damaged trees, with this increase in emissions due to alpha-pinene, beta-pinene, and camphene at both sites. During mid-summer, emission rates did not differ between previously damaged and undamaged trees at the site on the Western Slope of the Rocky Mountains, but rather tracked changes in the temperature and precipitation regime characteristic of the region. As the mid-summer drought progressed at the Eastern Slope site, emission rates were low, but differences between previously damaged and undamaged trees were not statistically significant. Despite no difference in emissions, mid-summer tissue monoterpene concentrations were significantly lower in previously damaged trees at both sites. With the onset of monsoon rains during late summer, emission rates from previously damaged trees increased to levels higher than those of undamaged trees despite the lack of herbivory. We conclude that (1) herbivory systemically increases the flux of terpenes to the atmosphere during the spring, (2) drought overrides the effect of past herbivory as the primary control over emissions during the mid-summer, and (3) a release from drought and the onset of late-summer rains is correlated with a secondary increase in emissions, particularly from herbivore-damaged trees, possibly due to a drought-delayed stimulation of induced monoterpene synthesis and/or increases in stomatal conductance. A greater understanding of the interactive effects of seasonality and herbivory on monoterpene emissions provides much needed information regarding the atmospheric and ecological consequences that these compounds will have for semiarid ecosystems.


Assuntos
Bálsamos/metabolismo , Clima , Herbivoria/fisiologia , Monoterpenos/química , Monoterpenos/metabolismo , Mariposas/fisiologia , Pinus/metabolismo , Extratos Vegetais/metabolismo , Animais , Secas , Larva/fisiologia , Estações do Ano , Fatores de Tempo , Árvores/classificação
12.
J Air Waste Manag Assoc ; : 1-12, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39189887

RESUMO

Airborne radioactivity from fossil fuel production systems is poorly characterized, but a recent study showed elevated ambient levels with proximity to oil and gas production wells. Here, we report year-long, high temporal resolution monitoring results of airborne alpha radioactivity from both radon gas and radon progeny attached to particulates immediately northeast of an oil refinery in Commerce City, Colorado, USA, in an environmental justice community of concern. Gas and particle-associated radioactivity contributed nearly evenly to the total alpha radioactivity. Total radioactivity levels of 30-40 Bq m-3 were 2-3 times higher than background levels (~10-15 Bq m-3) when winds were light and southwesterly, suggesting the refinery as the geographic origin. Furthermore, elevated airborne radioactivity tracked most closely with the light hydrocarbon and natural gas tracer ethane. Thus, the data imply natural gas as the radon emission carrier. Our findings are unique and suggest a need for further investigations of radon emissions from oil and gas infrastructure such as natural gas processing plants, compressor stations, petrochemical plants, and oil refineries that process oil and natural gas from unconventional production.Implications: Regulatory agencies currently do not mandate or conduct monitoring of radioactivity releases and public exposure from petroleum industry air emissions. This study reports elevated radioactivity from radon gas and nonvolatile radon decay products attached to particulate matter, at about 2-3 times above background levels in proximity to Colorado's largest oil refinery. Observations were within an environmental justice community of concern that experiences well above-average exposure to many other harmful atmospheric pollutants, suggesting potential adverse health effects from this cumulative exposure. Our findings offer actionable insights for policymakers, industry stakeholders, and affected communities alike.

13.
Mov Ecol ; 11(1): 28, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226200

RESUMO

Intra-specific variability in movement behaviour occurs in all major taxonomic groups. Despite its common occurrence and ecological consequences, individual variability is often overlooked. As a result, there is a persistent gap in knowledge about drivers of intra-specific variability in movement and its role in fulfilling life history requirements. We apply a context-focused approach to bull sharks (Carcharhinus leucas), a highly mobile marine predator, incorporating intra-specific variability to understand how variable movement patterns arise and how they might be altered under future change scenarios. Spatial analysis of sharks, acoustically tagged both at their distributional limit and the centre of distribution in southern Africa, was combined with spatial analysis of acoustically tagged teleost prey and remote-sensing of environmental variables. The objective was to test the hypothesis that varying resource availability and magnitude of seasonal environmental change in different locations interact to produce variable yet predictable movement behaviours across a species' distribution. Sharks from both locations showed high seasonal overlap with predictable prey aggregations. Patterns were variable in the centre of distribution, where residency, small- and large-scale movements were all recorded. In contrast, all animals from the distributional limit performed 'leap-frog migrations', making long-distance migrations bypassing conspecifics in the centre of distribution. By combining multiple variables related to life history requirements for animals in different environments we identified combinations of key drivers that explain the occurrence of differing movement behaviours across different contexts and delineated the effects of environmental factors and prey dynamics on predator movement. Comparisons with other taxa show striking similarities in patterns of intra-specific variability across terrestrial and marine species, suggesting common drivers.

14.
Biogeosciences ; 20(5): 971-995, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-39434786

RESUMO

Assessing nutrient critical load exceedances requires complete and accurate atmospheric deposition budgets for reactive nitrogen (Nr). The exceedance is the total amount of Nr deposited to the ecosystem in excess of the critical load, which is the amount of Nr input below which harmful effects do not occur. Total deposition includes all forms of Nr (i.e., organic and inorganic) deposited to the ecosystem by wet and dry pathways. Here we present results from the Southern Appalachian Nitrogen Deposition Study (SANDS), in which a combination of measurements and field-scale modeling was used to develop a complete annual Nr deposition budget for a deciduous forest at the Coweeta Hydrologic Laboratory. Wet deposition of ammonium, nitrate, nitrite, and bulk organic N were measured directly. The dry deposited Nr fraction was estimated using a bidirectional resistance-based model driven with speciated measurements of Nr air concentrations (e.g., ammonia, ammonium aerosol, nitric acid, nitrate aerosol, bulk organic N in aerosol, total alkyl nitrates, and total peroxy nitrates), micrometeorology, canopy structure, and biogeochemistry. Total annual deposition was ~6.7 kg N ha-1 yr-1, which is on the upper end of Nr critical load estimates recently developed for similar ecosystems in the nearby Great Smoky Mountains National Park. Of the total (wet + dry) budget, 51.1% was contributed by reduced forms of Nr NH x = ammonia + ammonium ) , with oxidized and organic forms contributing ~41.3% and 7.6%, respectively. Our results indicate that reductions in NH x deposition would be needed to achieve the lowest estimates (~3.0 kg N ha-1 yr-1) of Nr critical loads in southern Appalachian forests.

15.
J Cardiovasc Comput Tomogr ; 17(1): 66-83, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36216699

RESUMO

Cardio-Oncology is a rapidly growing sub-specialty of medicine, however, there is very limited guidance on the use of cardiac CT (CCT) in the care of Cardio-Oncology patients. In order to fill in the existing gaps, this Expert Consensus statement comprised of a multidisciplinary collaboration of experts in Cardiology, Radiology, Cardiovascular Multimodality Imaging, Cardio-Oncology, Oncology and Radiation Oncology aims to summarize current evidence for CCT applications in Cardio-Oncology and provide practice recommendations for clinicians.


Assuntos
Cardiologia , Neoplasias , Humanos , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X , Proteína Coestimuladora de Linfócitos T Induzíveis
16.
Ecol Evol ; 13(2): e9837, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36844667

RESUMO

The Bull Shark (Carcharhinus leucas) faces varying levels of exploitation around the world due to its coastal distribution. Information regarding population connectivity is crucial to evaluate its conservation status and local fishing impacts. In this study, we sampled 922 putative Bull Sharks from 19 locations in the first global assessment of population structure of this cosmopolitan species. Using a recently developed DNA-capture approach (DArTcap), samples were genotyped for 3400 nuclear markers. Additionally, full mitochondrial genomes of 384 Indo-Pacific samples were sequenced. Reproductive isolation was found between and across ocean basins (eastern Pacific, western Atlantic, eastern Atlantic, Indo-West Pacific) with distinct island populations in Japan and Fiji. Bull Sharks appear to maintain gene flow using shallow coastal waters as dispersal corridors, whereas large oceanic distances and historical land-bridges act as barriers. Females tend to return to the same area for reproduction, making them more susceptible to local threats and an important focus for management actions. Given these behaviors, the exploitation of Bull Sharks from insular populations, such as Japan and Fiji, may instigate local decline that cannot readily be replenished by immigration, which can in turn affect ecosystem dynamics and functions. These data also supported the development of a genetic panel to ascertain the population of origin, which will be useful in monitoring the trade of fisheries products and assessing population-level impacts of this harvest.

17.
Ecol Evol ; 12(7): e9128, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35898421

RESUMO

Despite its consequences for ecological processes and population dynamics, intra-specific variability is frequently overlooked in animal movement studies. Consequently, the necessary resolution to reveal drivers of individual movement decisions is often lost as animal movement data are aggregated to infer average or population patterns. Thus, an empirical understanding of why a given movement pattern occurs remains patchy for many taxa, especially in marine systems. Nonetheless, movement is often rationalized as being driven by basic life history requirements, such as acquiring energy (feeding), reproduction, predator-avoidance, and remaining in suitable environmental conditions. However, these life history requirements are central to every individual within a species and thus do not sufficiently account for the high intra-specific variability in movement behavior and hence fail to fully explain the occurrence of multiple movement strategies within a species. Animal movement appears highly context dependent as, for example, within the same location, the behavior of both resident and migratory individuals is driven by life history requirements, such as feeding or reproduction, however different movement strategies are utilized to fulfill them. A systematic taxa-wide approach that, instead of averaging population patterns, incorporates and utilizes intra-specific variability to enable predictions as to which movement patterns can be expected under a certain context, is needed. Here, we use intra-specific variability in elasmobranchs as a case study to introduce a stepwise approach for studying animal movement drivers that is based on a context-dependence framework. We examine relevant literature to illustrate how this context-focused approach can aid in reliably identifying drivers of a specific movement pattern. Ultimately, incorporating behavioral variability in the study of movement drivers can assist in making predictions about behavioral responses to environmental change, overcoming tagging biases, and establishing more efficient conservation measures.

18.
Front Public Health ; 10: 928575, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172210

RESUMO

Addressing mental health is an important part of the COVID-19 response among historically underserved communities, which have been disproportionately affected. Community Health Workers (CHWs) are well placed to offer insights about barriers to mental health service use in their communities, and they are well positioned to address mental health gaps by providing education, resources, and assistance to bridging the gap for the use of more traditional mental health services. Using the perspectives of CHWs, this project identified barriers faced by CHWs in assisting community members with their mental health needs, along with relevant training needs to more effectively deliver mental health resources, referrals, and recommendations to community members. Survey data along with data from focus groups were collected among 43 CHWs in communities that have been historically underserved near the U.S.-Mexico border region. Quantitative data were analyzed using descriptive statistics whereas qualitative data were analyzed through systematic methods. Identified barriers to assisting community members with their mental health needs exist at the personal, community, environmental and organizational levels, and ranged from fear and mistrust to limited services, resources, funding and training opportunities. To help address the aforementioned barriers and facilitate access to mental health service use in their communities, CHWs identified and described opportunities for training in core areas including communication, mental illness symptom identification, trauma, self-care and stress reduction, and cultural awareness and sensitivity. Needs-based training programs that incorporate the insights of CHWs are a crucial part of promoting community-based mental health to address existing mental health disparities in access to and use of mental health services.


Assuntos
COVID-19 , Agentes Comunitários de Saúde , COVID-19/epidemiologia , Agentes Comunitários de Saúde/psicologia , Hispânico ou Latino , Humanos , Saúde Mental , Pandemias , Pesquisa Qualitativa
19.
Sci Adv ; 8(33): eabo1754, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35984887

RESUMO

Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements.

20.
J Migr Health ; 4: 100058, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34405198

RESUMO

This study reviewed the methodology and findings of 44 peer-reviewed studies on psychosocial risk factors associated with mental health outcomes among undocumented immigrants (UIs) in the United States. Findings showed a considerable advancement over the past seven years in the methods and measures used in the included studies. Nonetheless, there is a need for continued methodological rigor, innovative study designs, greater diversity of samples, and in-depth exploration of constructs that facilitate resilience. Identifying avenues to reduce risk in this population is essential to inform intervention and advocacy efforts aimed at overcoming distress from the current U.S. anti-immigrant and socio-political climate.

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