RESUMEN
Permafrost and active layer studies are important to understand and predict regional climate changes. The objectives of this work were: i) to characterize the soil thermal regime (active layer thickness and permafrost formation) and its interannual variability and ii) to evaluate the influence of different climate variability modes to the observed soil thermal regime in a patterned ground soil in Maritime Antarctica. The study was carried out at Keller Peninsula, King George Island, Maritime Antarctica. Six soil temperatures probes were installed at different depths (10, 30 and 80cm) in the polygon center (Tc) and border (Tb) of a patterned ground soil. We applied cross-correlation analysis and standardized series were related to the Antarctic Oscillation Index (AAO). The estimated active layer thickness was approximately 0.75cm in the polygon border and 0.64cm in the center, indicating the presence of permafrost (within 80cm). Results indicate that summer and winter temperatures are becoming colder and warmer, respectively. Considering similar active layer thickness, the polygon border presented greater thawing days, resulting in greater vulnerability to warming, cooling faster than the center, due to its lower volumetric heat capacity (Cs). Cross-correlation analysis indicated statistically significant delay of 1day (at 10cm depth) in the polygon center, and 5days (at 80cm depth) for the thermal response between atmosphere and soil. Air temperature showed a delay of 5months with the climate variability models. The influence of southern winds from high latitudes, in the south facing slopes, favored freeze in the upper soil layers, and also contributed to keep permafrost closer to the surface. The observed cooling trend is linked to the regional climate variability modes influenced by atmospheric circulation, although longer monitoring period is required to reach a more precise scenario.
RESUMEN
RESUMO O Barbatimão (Stryphnodendron adstringens) planta medicinal encontrada no bioma Cerrado apresenta propriedades físico-químicas que lhe garante importantes atividades farmacológicas tais como: anti-inflamatória, analgésica e uma atividade protetora da mucosa gástrica. A casca do tronco é a principal matéria-prima usada para o desenvolvimento de produtos medicinais. Neste estudo, o objetivo foi investigar a influência da solução aquosa da casca do barbatimão no processo de formação de vasos sanguíneos na membrana corioalontoide de ovo embrionado de galinha. Foram utilizadas 30g da casca triturada em um litro de água. Este processo permitiu a obtenção da Solução Aquosa de Barbatimão - SAB em uma concentração de 30mg/mL. A atividade angiogênica da solução aquosa do barbatimão foi avaliada mediante realização de testes laboratoriais “in vivo”, utilizando como modelo experimental a membrana do ovo embrionado de galinha (MCA). Utilizou-se como controle indutor o Regederm®, o qual apresenta atividade angiogênica conhecida. Os resultados demonstraram que a SAB apresentou um percentual de vascularização na MCA de (50.4%) não tendo diferença (p>0,05) aos valores detectados no controle indutor (52,9%). Com os resultados obtidos, percebe-se que o barbatimão apresenta atividade angiogênica no modelo experimental utilizado.
ABSTRACT The Barbatimão (Stryphnodendron adstringens) medicinal plant found in the Cerrado biome has physicochemical properties which guarantee important pharmacological activities such as anti-inflammatic, analgesic and protective activities of gastric mucosa. The bark of the trunk is the main raw material used for the development of medicinal products. In this study, the objective was to investigate the influence of the aqueous solution of barbatimão bark in the formation of blood vessels in the membrane of embryonated chicken egg corioalontoid. 30g of shredded bark was used in one liter of water. This process enabled the obtention of aqueous Barbatimão - BSA at a concentration of 30mg / ml. The angiogenic activity of the aqueous solution of barbatimão was assessed by laboratory testing “in vivo”, using the chorioallantoic membrane of embryonated chicken egg (MCA) as an experimental model. TheRegederm® controlinductor was used, which exhibits known angiogenic activity. The results showed that the percentage of BSA showed a vascularization of the MCA (50.4%) there was no difference (p> 0.05) in the values detected in the control inductor (52.9%). With the obtained results, it is clear that barbatimão shows angiogenic activity under the experimental model used.
