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In the Deception and Livingston Islands, South Shetland Islands, Antarctica, two sites belonging to the international Circumpolar Active Layer Monitoring (CALM) network were established in 2005 and 2009, respectively, as part of the PERMATHERMAL network. In 2017, part of the installed instrumentation was upgraded, incorporating new CC5MPX automatic photographic cameras from Campbell Scientific to acquire three daily photographs at 5Mpx in resolution, 2592 × 1984 pixels in size, and JPEG format. The photographs are taken during the central hours of the day (14, 15, and 16 h GMT) to ensure maximum brightness, even during the Antarctic winter. Powered by batteries and solar panels, two cameras were installed at each site with a panoramic view, devoid of vegetation except for small patches of moss. At each study point, the cameras are oriented in different directions, providing diverse angles of the study area, and allowing observation of various fields of view in the environment. The result is a dataset of images acquired in the 2017-2022 period, organized by site, year, and month, capturing environmental conditions and spatial distribution of the snow cover. This dataset, besides documenting the snow cover, allows assessment of meteorological conditions, prevailing wind directions in the area during snow events, even in more distant areas from the study point due to the configured field of view. In the case of the images from Livingston Island, it also enables the study of the Limnopolar Lake's fluctuating water level during spring and summer. For the images from Deception Island, it provides insight into the presence of pack ice in Foster Port, relevant for volcanic activity and the safety of numerous vessels entering the caldera of the active volcano.
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BACKGROUND: Pruritus due to allergic skin disease is one of the most common reasons for dermatological consultations in the veterinary clinic. Treatment is usually multimodal and requires continuous monitoring and reassessment. New therapies are needed to broaden the therapeutic arsenal. HYPOTHESIS/OBJECTIVES: The aim of this study was to evaluate the efficacy of a novel transient receptor potential vanilloid 1 (TRPV1) channel antagonist for allergic pododermatitis in dogs. ANIMALS: Twenty-four client-owned dogs with allergic pododermatitis. MATERIALS AND METHODS: The study was an open, prospective, multi-centre clinical trial with client-owned dogs. All dogs were treated twice daily with a spray containing hydroxymethoxyiodobenzyl glycolamide pelargonate for 28 days. Clinical assessments included pruritus Visual Analog Scale (PVAS), pedal skin lesion score, evaluation of quality of life (QoL), presence of secondary infections and a four-point subjective efficacy assessment by the veterinarian and the dog owner. RESULTS: There was more than 50% improvement in all scores by the conclusion of the study. Secondary infections were reduced (p < 0.001). Both the veterinarians and dog owners evaluated the efficacy of the product positively. The product was well-tolerated. CONCLUSIONS AND CLINICAL RELEVANCE: This study demonstrated the tolerability and efficacy of a TRPV1 antagonist on pruritic pododermatitis in 24 dogs.
Assuntos
Coinfecção , Dermatite Atópica , Doenças do Cão , Hipersensibilidade , Humanos , Cães , Animais , Qualidade de Vida , Coinfecção/veterinária , Estudos Prospectivos , Prurido/tratamento farmacológico , Prurido/veterinária , Hipersensibilidade/veterinária , Dermatite Atópica/veterinária , Doenças do Cão/tratamento farmacológicoRESUMO
Permafrost controls geomorphological dynamics in maritime Antarctic ecosystems. Here, we analyze and model ground thermal regime in bordering conditions between continuous and discontinuous permafrost to better understand its relationship with the timing of glacial retreat. In February 2017, a transect including 10 sites for monitoring ground temperatures was installed in the eastern fringe of Byers Peninsula (Livingston Island, northern Antarctic Peninsula), together with one station recording air temperatures and snow thickness. The sites were selected following the Mid-Late Holocene deglaciation of the area at a distance ranging from 0.30 to 3.15â¯km from the current Rotch Dome glacier front. The transect provided data on the effects of topography, snow cover and the timing of ice-free exposure, on the ground thermal regime. From February 2017 to February 2019, the mean annual air temperature was -2.0⯰C, which was >0.5⯰C higher than 1986-2015 average in the Western Antarctic Peninsula region. Mean annual ground temperature at 10â¯cm depth varied between 0.3 and -1.1⯰C, similar to the modelled Temperatures on the Top of the Permafrost (TTOP) that ranged from 0.06⯱â¯0.08⯰C to -1.33⯱â¯0.07⯰C. The positive average temperatures at the warmest site were related to the long-lasting presence of snow which favoured warmer ground temperatures and may trigger permafrost degradation. The role of other factors (topography, and timing of the deglaciation) explained intersite differences, but the overall effect was not as strong as snow cover.
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Modelos Teóricos , Pergelissolo , Regiões Antárticas , Ecossistema , Camada de Gelo , IlhasRESUMO
The aim of this work is to investigate whether snow albedo seasonality and trend under all sky conditions at Johnsons Glacier (Livingston Island, Antarctica) can be tracked using the Moderate Resolution Imaging Spectroradiometer (MODIS) snow albedo daily product MOD10A1. The time span is from December 2006 to February 2015. As the MOD10A1 snow albedo product has never been used in Antarctica before, we also assess the performance for the MOD10A1 cloud mask. The motivation for this work is the need for a description of snow albedo under all sky conditions (including overcast days) using satellite data with mid-spatial resolution. In-situ albedo was filtered with a 5-day windowed moving average, while the MOD10A1 data were filtered using a maximum filter. Both in-situ and MOD10A1 data follow an exponential decay during the melting season, with a maximum decay of 0.049/0.094 day-1 (in-situ/MOD10A1) for the 2006-2007 season and a minimum of 0.016/0.016 day-1 for the 2009-2010 season. The duration of the decay varies from 85 days (2007-2008) to 167 days (2013-2014). Regarding the albedo trend, both data sets exhibit a slight increase of albedo, which may be explained by an increase of snowfall along with a decrease of snowmelt in the study area. Annual albedo increases of 0.2% and 0.7% are obtained for in-situ and MOD10A1 data, respectively, which amount to respective increases of 2% and 6% in the period 2006-2015. We conclude that MOD10A1 can be used to characterize snow albedo seasonality and trend on Livingston Island when filtered with a maximum filter.
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The Antarctic Peninsula has had a globally large increase in mean annual temperature from the 1951 to 1998 followed by a decline that still continues. The challenge is now to unveil whether these recent, complex and somewhat unexpected climatic changes are biologically relevant. We were able to do this by determining the growth of six lichen species on recently deglaciated surfaces over the last 24 years. Between 1991 and 2002, when mean summer temperature (MST) rose by 0.42 °C, five of the six species responded with increased growth. MST declined by 0.58 °C between 2002 and 2015 with most species showing a fall in growth rate and two of which showed a collapse with the loss of large individuals due to a combination of increased snow fall and longer snow cover duration. Increased precipitation can, counter-intuitively, have major negative effects when it falls as snow at cooler temperatures. The recent Antarctic cooling is having easily detectable and deleterious impacts on slow growing and highly stress-tolerant crustose lichens, which are comparable in extent and dynamics, and reverses the gains observed over the previous decades of exceptional warming.