Geophysical and atmospheric evolution of habitable planets

The evolution of Earth-like habitable planets is a complex process that depends on the geodynamical and geophysical environments. In particular, it is necessary that plate tectonics remain active over billions of years. These geophysically active environments are strongly coupled to a planet's host star parameters, such as mass, luminosity and activity, orbit location of the habitable zone, and the planet's initial water inventory. Depending on the host star's radiation and particle flux evolution, the composition in the thermosphere, and the availability of an active magnetic dynamo, the atmospheres of Earth-like planets within their habitable zones are differently affected due to thermal and nonthermal escape processes. For some planets, strong atmospheric escape could even effect the stability of the atmosphere

Tissue injuries of wistar rats treated with hydroalcoholic extract of Sonchus oleraceus L.

The use of plant species is emerging as an important alternative in the treatment of injuries. Therefore, the extract of Sonchus oleraceus 10% was employed in the repair of skin lesions. A total of 36 male Wistar rats were subjected to a punch injury and divided into three groups: a negative control, receiving no treatment, a positive control, treated with Dersani, and the experimental group treated with the extract. The injury was assessed macroscopically and microscopically. Morphometric data was collected at the 3rd, 5th and 7th postoperative day, and the experimental group showed greater changes in shrinkage of the lesion compared to control groups. On the 3rd postoperative day, the injury in the experimental group showed less necrotic tissue, lower slough and more granulation tissue in relation to the positive control group. On the 7th and 10th postoperative day, the injury in the experimental group showed lower slough compared to the positive control group. Microscopic analysis of lesions on the 5th postoperative day revealed increased fibroplasia in the experimental group compared to control groups, while on the 14th postoperative day less neovascularization was evident in the experimental group and increased formation of hair follicles in the negative control group. The extract of S. oleraceus provided tissue repair in accordance with normal physiological patterns thus confirming empirical evidence for its use.<br>O emprego de espécies vegetais vem surgindo como alternativa no tratamento de lesões. Dessa forma, foi utilizado o extrato hidroalcoólico de Sonchus oleraceus a 10% na reparação de lesões cutâneas. Trinta e seis ratos machos Wistar, foram submetidos a uma lesão com "punch" e distribuídos em três grupos: controle negativo, não recebeu tratamento; controle positivo, tratado com Dersani; e o experimental, tratado com extrato. A lesão foi avaliada macroscopicamente e microscopicamente. Os dados morfométricos mostraram que no 3º, 5º e 7º dia pós-operação (DPO), o grupo experimental apresentou maior evolução na retração da lesão em relação aos grupos controles. No 3° DPO a lesão do grupo experimental apresentou menor tecido necrótico, menor esfacelo e maior tecido de granulação em relação ao grupo controle positivo. No 7° e 10º DPO, a lesão do grupo experimental apresentou menor esfacelo em relação ao grupo controle positivo. A análise microscópica das lesões revelou no 5º DPO maior fibroplasia no grupo experimental em relação aos grupos controles; no 14º DPO ocorreu menor neovascularização no grupo experimental e maior formação de folículos pilosos no grupo controle negativo. O extrato hidroalcoólico de S. oleraceus propiciou reparo tecidual obedecendo a padrões fisiológicos normais e confirmando os dados empíricos de sua utilização