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1.
Proc Biol Sci ; 291(2023): 20240454, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38807519

RESUMO

Challenges imposed by geographical barriers during migration are selective agents for animals. Juvenile soaring landbirds often cross large water bodies along their migratory path, where they lack updraft support and are vulnerable to harsh weather. However, the consequences of inexperience in accomplishing these water crossings remain largely unquantified. To address this knowledge gap, we tracked the movements of juvenile and adult black kites Milvus migrans over the Strait of Gibraltar using high-frequency tracking devices in variable crosswind conditions. We found that juveniles crossed under higher crosswind speeds and at wider sections of the strait compared with adults during easterly winds, which represent a high risk owing to their high speed and steady direction towards the Atlantic Ocean. Juveniles also drifted extensively with easterly winds, contrasting with adults who strongly compensated for lateral displacement through flapping. Age differences were inconspicuous during winds with a west crosswind speed component, as well as for airspeed modulation in all wind conditions. We suggest that the suboptimal sea-crossing behaviour of juvenile black kites may impact their survival rates, either by increasing chances of drowning owing to exhaustion or by depleting critical energy reserves needed to accomplish their first migration.


Assuntos
Migração Animal , Vento , Animais , Fatores Etários , Falconiformes/fisiologia , Voo Animal , Oceano Atlântico
2.
Bull Entomol Res ; 112(2): 143-150, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34486961

RESUMO

In different parts of the world, aphid populations and their natural enemies are influenced by landscapes and climate. In the Neotropical region, few long-term studies have been conducted, maintaining a gap for comprehension of the effect of meteorological variables on aphid population patterns and their parasitoids in field conditions. This study describes the general patterns of oscillation in cereal winged aphids and their parasitoids, selecting meteorological variables and evaluating their effects on these insects. Aphids exhibit two annual peaks, one in summer-fall transition and the other in winter-spring transition. For parasitoids, the highest annual peak takes place during winter and a second peak occurs in winter-spring transition. Temperature was the principal meteorological regulator of population fluctuation in winged aphids and parasitoids during the year. The favorable temperature range is not the same for aphids and parasitoids. For aphids, temperature increase resulted in population growth, with maximum positive effect at 25°C. Temperature also positively influenced parasitoid populations, but the growth was asymptotic around 20°C. Although rainfall showed no regulatory function on aphid seasonality, it influenced the final number of insects over the year. The response of aphids and parasitoids to temperature has implications for trophic compatibility and regulation of their populations. Such functions should be taken into account in predictive models.


Assuntos
Afídeos , Animais , Afídeos/fisiologia , Brasil , Clima , Grão Comestível , Estações do Ano
3.
J Anim Ecol ; 89(1): 93-103, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30762229

RESUMO

Wind energy production has expanded to meet climate change mitigation goals, but negative impacts of wind turbines have been reported on wildlife. Soaring birds are among the most affected groups with alarming fatality rates by collision with wind turbines and an escalating occupation of their migratory corridors. These birds have been described as changing their flight trajectories to avoid wind turbines, but this behaviour may lead to functional habitat loss, as suitable soaring areas in the proximity of wind turbines will likely be underused. We modelled the displacement effect of wind turbines on black kites (Milvus migrans) tracked by GPS. We also evaluated the impact of this effect at the scale of the landscape by estimating how much suitable soaring area was lost to wind turbines. We used state-of-the-art tracking devices to monitor the movements of 130 black kites in an area populated by wind turbines, at the migratory bottleneck of the Strait of Gibraltar. Landscape use by birds was mapped from GPS data using dynamic Brownian bridge movement models, and generalized additive mixed modelling was used to estimate the effect of wind turbine proximity on bird use while accounting for orographic and thermal uplift availability. We found that areas up to approximately 674 m away from the turbines were less used than expected given their uplift potential. Within that distance threshold, bird use decreased with the proximity to wind turbines. We estimated that the footprint of wind turbines affected 3%-14% of the areas suitable for soaring in our study area. We present evidence that the impacts of wind energy industry on soaring birds are greater than previously acknowledged. In addition to the commonly reported fatalities, the avoidance of turbines by soaring birds causes habitat losses in their movement corridors. Authorities should recognize this further impact of wind energy production and establish new regulations that protect soaring habitat. We also showed that soaring habitat for birds can be modelled at a fine scale using publicly available data. Such an approach can be used to plan low-impact placement of turbines in new wind energy developments.


Assuntos
Aves , Voo Animal , Animais , Mudança Climática , Ecossistema
4.
Eur J Neurosci ; 40(7): 3102-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25039270

RESUMO

The importance of the vertebrate hippocampus in spatial cognition is often related to its broad role in memory. However, in birds, the hippocampus appears to be more specifically involved in spatial processes. The maturing of GPS-tracking technology has enabled a revolution in navigation research, including the expanded possibility of studying brain mechanisms that guide navigation in the field. By GPS-tracking homing pigeons released from distant, unfamiliar sites prior to and after hippocampal lesion, we observed, as has been reported previously, impaired navigational performance post-lesion over the familiar/memorized space near the home loft, where topographic features constitute an important source of navigational information. The GPS-tracking revealed that many of the lost pigeons, when lesioned, approached the home area, but nevertheless failed to locate their loft. Unexpectedly, when they were hippocampal-lesioned, the pigeons showed a notable change in their behaviour when navigating over the unfamiliar space distant from home; they actually flew straighter homeward-directed paths than they did pre-lesion. The data are consistent with the hypothesis that, following hippocampal lesion, homing pigeons respond less to unfamiliar visual, topographic features encountered during homing, and, as such, offer the first evidence for an unforeseen, perceptual neglect of environmental features following hippocampal damage.


Assuntos
Hipocampo/fisiologia , Comportamento de Retorno ao Território Vital/fisiologia , Percepção Espacial/fisiologia , Navegação Espacial/fisiologia , Animais , Columbidae , Sistemas de Informação Geográfica , Hipocampo/patologia , Transtornos da Percepção/etiologia
5.
Sci Total Environ ; 858(Pt 1): 159707, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306834

RESUMO

Shorebird declines are occurring worldwide but the causes are not fully understood. Recent literature suggests that the deterioration of habitat quality at their non-breeding areas, mostly located in temperate and tropical coastal wetlands, might be a major contributing factor. However, most studies carried out so far tend to be restricted to a few regions. Remote sensing can help correct such geographical bias on knowledge by providing a standardized approach on how shorebird habitats have been changing over the last few decades at a global scale. Here we analyzed time series of remote sensing classifications of tidal flats and land cover to quantify worldwide habitat changes in coastal Important Bird and Biodiversity Areas (IBAs) relevant for non-breeding shorebirds over the last two decades. Globally, supratidal areas (used as roosting habitat) have changed more significantly than tidal flats (used as feeding habitat). Yet, we found striking losses of tidal flats in IBAs distributed in several regions of the East Asian - Australasian Flyway. At supratidal areas, there was a general expansion of marshland, grassland and urban areas, contrasting with a decline of barren land, woodland and cropland. The expansion of marshland occurred in IBAs of most regions of the world. Urban areas also expanded consistently in supratidal areas within the most populated regions of the world. The loss of barren land is particularly concerning as it may translate into a loss of high-quality roosts and it was highly frequent in IBAs of all migratory flyways. Overall, our results confirm the large losses of shorebird habitat in the East Asian - Australasian Flyway reported in the literature, and highlight unreported generalized changes in supratidal habitats, such as the expansion of marshland and the loss of barren land, that may have negative implications for shorebirds, deserving further research and consideration in conservation programs.


Assuntos
Ecossistema , Áreas Alagadas , Animais , Aves , Biodiversidade , Geografia , Conservação dos Recursos Naturais
6.
Curr Biol ; 33(6): 1179-1184.e3, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36827987

RESUMO

Storms can cause widespread seabird stranding and wrecking,1,2,3,4,5 yet little is known about the maximum wind speeds that birds are able to tolerate or the conditions they avoid. We analyzed >300,000 h of tracking data from 18 seabird species, including flapping and soaring fliers, to assess how flight morphology affects wind selectivity, both at fine scales (hourly movement steps) and across the breeding season. We found no general preference or avoidance of particular wind speeds within foraging tracks. This suggests seabird flight morphology is adapted to a "wind niche," with higher wing loading being selected in windier environments. In support of this, wing loading was positively related to the median wind speeds on the breeding grounds, as well as the maximum wind speeds in which birds flew. Yet globally, the highest wind speeds occur in the tropics (in association with tropical cyclones) where birds are morphologically adapted to low median wind speeds. Tropical species must therefore show behavioral responses to extreme winds, including long-range avoidance of wind speeds that can be twice their operable maxima. By contrast, Procellariiformes flew in almost all wind speeds they encountered at a seasonal scale. Despite this, we describe a small number of cases where albatrosses avoided strong winds at close range, including by flying into the eye of the storm. Extreme winds appear to pose context-dependent risks to seabirds, and more information is needed on the factors that determine the hierarchy of risk, given the impact of global change on storm intensity.6,7.


Assuntos
Voo Animal , Vento , Animais , Voo Animal/fisiologia , Aves/fisiologia , Adaptação Fisiológica , Comportamento Alimentar/fisiologia
7.
Sci Total Environ ; 836: 155679, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35523322

RESUMO

Saltwater intrusion can dramatically transform coastal ecosystems, changing vegetation and impacting wildlife and human communities who rely on these natural resources. This phenomenon is difficult to measure over large and remote areas but can be inferred from changes in the distribution of salt-tolerant vegetation, such as mangroves, observable from satellite imagery. The northern coast of Brazil has the largest continuous mangrove forest in the world and very low human occupation. Even so, saltwater intrusion and changes to the coastline have been reported in this region, with potential consequences for mangrove carbon storage and for local livelihoods, but this has not been quantified due to the remoteness of the area. This study measured changes in mangrove distribution along the Northern Brazil coast in the state of Amapá, covering ca. 15,000 km2, over the last 38 years using Landsat satellite imagery. We found that mangrove area in this region is highly dynamic, with significant gains and losses occurring over the study period, but with an overall net gain of 157 km2. Mangroves have been systematically expanding inland and this growth has accelerated close to the shoreline and at the head of tidal channels in the last two decades, indicating rapid and large-scale saltwater intrusion in this region. This phenomenon is likely driven by sea level rise, which also accelerated in this region in recent decades, but anthropogenic impacts such as buffalo grazing may also play an important role.


Assuntos
Ecossistema , Áreas Alagadas , Carbono , Mudança Climática , Imagens de Satélites , Elevação do Nível do Mar
8.
Sci Rep ; 12(1): 6441, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440704

RESUMO

Wind energy production has expanded as an alternative to carbon emitting fossil fuels, but is causing impacts on wildlife that need to be addressed. Soaring birds show concerning rates of collision with turbine rotor blades and losses of critical habitat. However, how these birds interact with wind turbines is poorly understood. We analyzed high-frequency GPS tracking data of 126 black kites (Milvus migrans) moving near wind turbines to identify behavioural mechanisms of turbine avoidance and their interaction with environmental variables. Birds flying within 1000 m from turbines and below the height of rotor blades were less likely to be oriented towards turbines than expected by chance, this pattern being more striking at distances less than 750 m. Within the range of 750 m, birds showed stronger avoidance when pushed by the wind in the direction of the turbines. Birds flying above the turbines did not change flight directions with turbine proximity. Sex and age of birds, uplift conditions and turbine height, showed no effect on flight directions although these factors have been pointed as important drivers of turbine collision by soaring birds. Our findings suggest that migrating black kites recognize the presence of wind turbines and behave in a way to avoid then. This may explain why this species presents lower collision rates with wind turbines than other soaring birds. Future studies should clarify if turbine avoidance behaviour is common to other soaring birds, particularly those that are facing high fatality rates due to collision.


Assuntos
Aprendizagem da Esquiva , Aves , Animais , Animais Selvagens , Ecossistema
9.
PLoS One ; 15(11): e0242662, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33226991

RESUMO

The disturbance of wildlife by humans is a worldwide phenomenon that contributes to the loss of biodiversity. It can impact animals' behaviour and physiology, and this can lead to changes in species distribution and richness. Wildlife disturbance has mostly been assessed through direct observation. However, advances in bio-logging provide a new range of sensors that may allow measuring disturbance of animals with high precision and remotely, and reducing the effects of human observers. We used tri-axial accelerometers to identify daytime flights of roosting straw-coloured fruit bats (Eidolon helvum), which were used as a proxy for roost disturbance. This bat species roosts on trees in large numbers (often reaching hundreds of thousands of animals), making them highly vulnerable to disturbance. We captured and tagged 46 straw-coloured fruit bats with dataloggers, containing a global positioning system (GPS) and an accelerometer, in five roosts in Ghana, Burkina Faso and Zambia. Daytime roost flights were identified from accelerometer signatures and modelled against our activity in the roosts during the days of trapping, as a predictor of roost disturbance, and natural stressors (solar irradiance, precipitation and wind speed). We found that daytime roost flight probability increased during days of trapping and with increasing solar irradiance (which may reflect the search for shade to prevent overheating). Our results validate the use of accelerometers to measure roost disturbance of straw-coloured fruit bats and suggest that these devices may be very useful in conservation monitoring programs for large fruit bat species.


Assuntos
Migração Animal/fisiologia , Quirópteros/fisiologia , Comportamento de Retorno ao Território Vital/fisiologia , África Subsaariana , Animais , Comportamento Animal , Humanos
10.
Artigo em Espanhol | MEDLINE | ID: mdl-21190631

RESUMO

Wegener's granulomatosis is a granulomatous necrotizing vasculitis which predominantly affects the respiratory tract, kidney, and less frequently other organs such as the nervous system. The latter may occur in up to 54% of cases and when it does it is more frequently of the peripheral nerves. We present a 19 year old woman who commenced her disease with involvement of respiratory sinuses, lungs and kidney and who developed central insipid diabetes (CID) at onset. The CID persisted in spite of adequate response of the other organs and systems with immunosuppresor treatment. The development of CID in the context of vasculitis should suggest this as a possible mechanism.


Assuntos
Diabetes Insípido Neurogênico/etiologia , Granulomatose com Poliangiite/complicações , Feminino , Humanos , Adulto Jovem
11.
PeerJ ; 7: e6261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30671305

RESUMO

BACKGROUND: The introduction of animal tracking technology has rapidly advanced our understanding of seabird foraging ecology. Tracking data is particularly powerful when combined with oceanographic information derived from satellite remote sensing, allowing insights into the functional mechanisms of marine ecosystems. While this framework has been used extensively over the last two decades, there are still vast ocean regions and many seabird species for which information is scarce, particularly in tropical oceans. METHODS: In this study we tracked the movement at high GPS recording frequency of 15 White-tailed Tropicbirds (Phaethon lepturus) during chick-rearing from a colony in Fernando de Noronha (offshore of Northeast Brazil). Flight behaviours of travelling and searching for food were derived from GPS data and examined in relation to satellite-sensed oceanographic variables (sea surface temperature, turbidity and chlorophyll-a concentration). RESULTS: White-tailed Tropicbirds showed marked preference for clear and warm sea surface waters, which are indicative of low primary productivity but are likely the best habitat for preying upon flying fish. DISCUSSION: These findings are consistent with previous studies showing that foraging habitat choices of tropical seabirds may not be driven by primary productivity, as has been widely shown for non-tropical species.

12.
Sci Rep ; 7(1): 6421, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743947

RESUMO

Understanding how soaring birds use updrafts at small spatial scales is important to identify ecological constraints of movement, and may help to prevent conflicts between wind-energy development and the conservation of wildlife. We combined high-frequency GPS animal tracking and fine-spatial-scale uplift modelling to establish a link between flight behaviour of soaring birds and the distribution of updrafts. We caught 21 black kites (Milvus migrans) and GPS-tracked them while flying over the Tarifa region, on the Spanish side of the Strait of Gibraltar. This region has a diverse topography and land cover, favouring a heterogeneous updraft spatial distribution. Bird tracks were segmented and classified into flight modes from motion parameters. Thermal and orographic uplift velocities were modelled from publically available remote-sensing and meteorological data. We found that birds perform circular soaring in areas of higher predicted thermal uplift and linear soaring in areas of higher predicted orographic uplift velocity. We show that updraft maps produced from publically available data can be used to predict where soaring birds will concentrate their flight paths and how they will behave in flight. We recommend the use of this methodological approach to improve environmental impact assessments of new wind-energy installations.


Assuntos
Falconiformes/fisiologia , Voo Animal/fisiologia , Animais , Sistemas de Informação Geográfica , Modelos Biológicos , Espanha
13.
PLoS One ; 11(2): e0147497, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26863416

RESUMO

Social animals routinely are challenged to make consensus decisions about movement directions and routes. However, the underlying mechanisms facilitating such decision-making processes are still poorly known. A prominent question is how group members participate in group decisions. We addressed this question by examining how flocks of homing pigeons (Columba livia) decide their homing direction. We released newly formed flocks varying in size and determined the time taken to choose a homing direction (decision-making period) and the accuracy of that choice. We found that the decision-making period increases exponentially with flock size, which is consistent with a participatory decision-making process. We additionally found that there is no effect of flock size on the accuracy of the decisions made, which does not match with current theory for democratic choices of flight directions. Our combined results are better explained by a participatory choice of leaders that subsequently undertake the flock directional decisions. However, this decision-making model would only entirely fit with our results if leaders were chosen based on traits other than their navigational experience. Our study provides rare empirical evidence elucidating decision-making processes in freely moving groups of animals.


Assuntos
Comportamento de Escolha , Columbidae/fisiologia , Comportamento de Retorno ao Território Vital , Comportamento de Massa , Animais , Estrutura de Grupo , Modelos Psicológicos , Predomínio Social , Fatores de Tempo
14.
Rev. psicol. organ. trab ; 20(3): 1157-1165, jul.-set. 2020. ilus, tab
Artigo em Português | LILACS-Express | LILACS, INDEXPSI | ID: biblio-1127191

RESUMO

Os aplicativos de economia compartilhada impulsionaram um novo modelo de trabalho e um novo perfil de trabalhador. Considerando tal realidade, o presente estudo buscou identificar os principais motivadores de engajamento como trabalhador em plataformas de mobilidade urbana, mais especificamente de compartilhamento de carona (ridesharing). Em concomitância, investigou-se a influência de fatores socioeconômicos na relevância dos diferentes motivadores. Participaram da pesquisa quarenta e três motoristas de aplicativos, por meio online, a partir do aplicativo denominado Google Formulários. Para a análise de dados foi utilizado o modelo estatístico de regressão múltipla. Nos resultados encontrados, os motivadores considerados os mais relevantes para a escolha dos participantes foram Autonomia, Renda e Horário Flexível. Dos catorze motivadores investigados, dez apresentaram interações estatisticamente significativas com aspectos socioeconômicos. Os resultados também apontam diferenças entre os motivadores considerados como mais relevantes pelos participantes, quando comparados com estudos realizados em outros países. Salienta-se, portanto, a necessidade de um olhar diferenciado para a realidade brasileira.


Sharing economy applications have boosted a new work model and worker profile. The present study aimed to identify the main worker's motivators for engagement in urban mobility platforms, specifically in ridesharing applications. The influence of socioeconomic factors on the relevance of motivators was also investigated. Data was collected using an online survey from 43 drivers who work through applications. A multiple regression model was used for data analysis. The results showed that the most important motivators indicated by the participants were autonomy, income, and having flexible schedules. 10 out of the 14 motivators studied had significant interactions with socioeconomic aspects. The results also point out differences between the motivators considered most relevant by the participants, when compared to studies carried out in other countries. Therefore, a specific approach to this topic which is compatible with the Brazilian reality is needed.


Los aplicativos de movilidad urbana impulsaron un nuevo modelo de trabajo y un nuevo perfil de trabajadores. Considerando tal realidad, este estudio buscó identificar los principales motivadores de la participación como trabajador en plataformas de movilidad urbana, más específicamente de viajes compartidos. En concomitancia, fue investigada la influencia de los factores socioeconómicos en la relevancia de los diferentes motivadores. Participaron de la pesquisa cuarenta y tres conductores de aplicativos, por medio on line, a través del aplicativo denominado Google Formulários. Para el análisis de datos, se utilizó el modelo estadístico de regresión múltiple. Según los resultados, los motivadores considerados más relevantes para los participantes fueron Autonomía, Ingresos y Horas Flexibles. De los catorce motivadores investigados, diez tuvieron interacciones estadísticamente significativas con aspectos socioeconómicos. Comparado con estudios realizados en otros países, los resultados mostraron diferencias entre los motivadores mas relevantes. Por lo tanto, se enfatiza la necesidad de una mirada diferente, ajustada a la realidad brasileña.

15.
Sci Rep ; 5: 15490, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26489437

RESUMO

Personality traits have recently been shown to impact fitness in different animal species, potentially making them similarly relevant drivers as morphological and life history traits along the evolutionary pathways of organisms. Predation is a major force of natural selection through its deterministic effects on individual survival, but how predation pressure has helped to shape personality trait selection, especially in free-ranging animals, remains poorly understood. We used high-precision GPS tracking to follow whole flocks of homing pigeons (Columba livia) with known personalities and morphology during homing flights where they were severely predated by raptors. This allowed us to determine how the personality and morphology traits of pigeons may affect their risk of being predated by raptors. Our survival model showed that individual pigeons, which were more tolerant to human approach, slower to escape from a confined environment, more resistant to human handling, with larger tarsi, and with lighter plumage, were more likely to be predated by raptors. We provide rare empirical evidence that the personality of prey influences their risk of being predated under free-ranging circumstances.


Assuntos
Comportamento Animal , Columbidae/fisiologia , Personalidade/genética , Comportamento Predatório/fisiologia , Animais , Columbidae/genética , Sistemas de Informação Geográfica , Humanos , Personalidade/fisiologia , Aves Predatórias/fisiologia
16.
PLoS One ; 9(7): e102771, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25054203

RESUMO

Organized flight of homing pigeons (Columba livia) was previously shown to rely on simple leadership rules between flock mates, yet the stability of this social structuring over time and across different contexts remains unclear. We quantified the repeatability of leadership-based flock structures within a flight and across multiple flights conducted with the same animals. We compared two contexts of flock composition: flocks of birds of the same age and flight experience; and, flocks of birds of different ages and flight experience. All flocks displayed consistent leadership-based structures over time, showing that individuals have stable roles in the navigational decisions of the flock. However, flocks of balanced age and flight experience exhibited reduced leadership stability, indicating that these factors promote flock structuring. Our study empirically demonstrates that leadership and followership are consistent behaviours in homing pigeon flocks, but such consistency is affected by the heterogeneity of individual flight experiences and/or age. Similar evidence from other species suggests leadership as an important mechanism for coordinated motion in small groups of animals with strong social bonds.


Assuntos
Columbidae/fisiologia , Voo Animal/fisiologia , Hierarquia Social , Comportamento de Retorno ao Território Vital/fisiologia , Orientação/fisiologia , Animais , Predomínio Social , Fatores de Tempo
17.
Surg. cosmet. dermatol. (Impr.) ; 11(1): 26-30, Jan.-Mar. 2019. ilus, tab
Artigo em Inglês, Português | LILACS | ID: biblio-1008239

RESUMO

Introdução: A queratose actínica (QA) é lesão pré-maligna que pode progredir para carcinoma espinocelular. O diagnóstico é clínico, dermatoscópico e por microscopia confocal. Atualmente, aborda-se o tratamento do campo cancerizável, abrangendo QAs clinicamente visíveis e subclínicas, sendo a terapia fotodinâmica (PDT) uma opção terapêutica. Objetivo: Avaliar melhora das QAs e campo cancerizável em pacientes submetidos a PDT com luz do dia, com análise clínica, dermatoscópica e por microscopia confocal. Métodos: Foram selecionados dez pacientes, com múltiplas QAs na face. Realizada a PDT utilizando luz do dia com aminolevulinato de metila e feita documentação fotográfica clínica, dermatoscópica e por microscopia confocal antes do tratamento e 60 dias após seu início. Resultados: Dos nove pacientes que completaram o tratamento, oito (88,8%) apresentaram melhora clínica e regressão no grau da QA com uma sessão. Na dermatoscopia, quatro pacientes (44,4%) apresentaram melhora significativa, três pacientes (33,3%) apresentaram melhora parcial e dois pacientes (22,2%) tiveram suas lesões estáveis. Na microscopia confocal, seis (66,6%) pacientes tiveram regressão no grau da lesão. Conclusões: A PDT com luz do dia se mostrou eficaz para tratamento de QAs, apresentando alto grau de tolerabilidade e eficácia, além de bom perfil de segurança.


Introduction: Actinic keratosis (AK) is a pre-malignant lesion that can progress to squamous cell carcinoma. The diagnosis is through clinical, dermatoscopic and confocal microscopy assessment. Currently, the approach is the treatment of the field cancerization, comprising of clinically visible and subclinical AKs, for which photodynamic therapy (PDT) is a therapeutic option. Objective: To evaluate improvement of AKs and cancerization field in patients submitted to daylight PDT, with clinical, dermatoscopic and confocal microscopy assessment. Methods: Ten patients with multiple AKs on the face were selected. Daylight PDT was performed using methyl aminolevulinate and clinical, dermatoscopic and confocal microscopy photographic documentation was performed before and 60 days after the treatment. Results: Of the nine patients who completed the treatment, 8 (88.8%) showed clinical improvement and reduction in the severity of AK with one treatment. On dermatoscopy, 4 patients (44.4%) showed significant improvement, 3 patients (33.3%) showed partial improvement and 2 patients (22.2%) had no change. On confocal microscopy, 6 (66.6%) patients presented reduction in the severity of the lesion. Conclusions: Daylight PDT proved to be effective for the treatment of AKs, with high tolerability and efficacy, besides a good safety profile.


Assuntos
Métodos , Fotoquimioterapia , Microscopia Confocal , Dermoscopia , Ceratose Actínica
18.
PLoS One ; 8(12): e81174, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24312532

RESUMO

During the annual cycle, migratory waders may face strikingly different feeding conditions as they move between breeding areas and wintering grounds. Thus, it is of crucial importance that they rapidly adjust their behaviour and diet to benefit from peaks of prey abundance, in particular during migration, when they need to accumulate energy at a fast pace. In this study, we compared foraging behaviour and diet of wintering and northward migrating dunlins in the Tagus estuary, Portugal, by video-recording foraging birds and analysing their droppings. We also estimated energy intake rates and analysed variations in prey availability, including those that were active at the sediment surface. Wintering and northward migrating dunlins showed clearly different foraging behaviour and diet. In winter, birds predominantly adopted a tactile foraging technique (probing), mainly used to search for small buried bivalves, with some visual surface pecking to collect gastropods and crop bivalve siphons. Contrastingly, in spring dunlins generally used a visual foraging strategy, mostly to consume worms, but also bivalve siphons and shrimps. From winter to spring, we found a marked increase both in the biomass of invertebrate prey in the sediment and in the surface activity of worms and siphons. The combination of these two factors, together with the availability of shrimps in spring, most likely explains the changes in the diet and foraging behaviour of dunlins. Northward migrating birds took advantage from the improved feeding conditions in spring, achieving 65% higher energy intake rates as compared with wintering birds. Building on these results and on known daily activity budgets for this species, our results suggest that Tagus estuary provides high-quality feeding conditions for birds during their stopovers, enabling high fattening rates. These findings show that this large wetland plays a key role as a stopover site for migratory waders within the East Atlantic Flyway.


Assuntos
Migração Animal/fisiologia , Charadriiformes/fisiologia , Estuários , Comportamento Alimentar/fisiologia , Estações do Ano , Animais , Europa (Continente)
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