Plantas medicinais utilizadas pelos octogenários e nonagenários de uma vila periférica de Rio Grande/RS, Brasil.

Objetivo: resgatar o conhecimento de práticas de utilização de plantas medicinais de uma população idosa de Rio Grande/RS. Metodologia: estudo qualitativo, vinculado ao projeto ?Plantas bioativas de uso humano por famílias de agricultores de base ecológica na região Sul (RS)?, submetido ao Comitê de Ética da Faculdade de Medicina da Universidade Federal de Pelotas, protocolo 072/2007. A coleta de dados ocorreu de abril a julho de 2010. Os sujeitos foram selecionados através de entrevistas semi-estruturadas pela equipe de Saúde da Família, ambos da periferia de Rio Grande/RS. Apenas 12 dos 36 octogenários e nonagenários entrevistados haviam desenvolvido atividades agrícolas. Resultados: foram citadas 34 plantas medicinais, muitas delas são para curar resfriados. Em 28 observações, a folha foi a parte mais citada. Conclusão: é importante resgatar estas informações dos idosos, pois elas podem perder-se caso eles venham a falecer e não relatem estes saberes

DNA extraction and purification from species of Tabebuia aurea and T. ochracea (Bignoniaceae).

Edição dos resumos do 45º Congresso Nacional de Genética, Gramado, 1999

Reproductive cycle of Bolinus brandaris (Gastropoda: Muricidae) in the Gulf of Gabes (southern Tunisia)

The reproductive cycle of the purple dye murex (Bolinus brandaris) from the Gulf of Gabes was studied through gonad histology and calculation of bio-physiological indices (general condition index - K and gonadosomatic index - GSI). The shell length at first sexual maturity (SL50) of B. brandaris was also investigated using a macroscopic maturation scale. The population's sex ratio was statistically skewed (M:F = 1:1.5), with a significant dominance of females over males. Monthly variations in the maturation stages of gonads, K and GSI showed that B. brandaris has an annual reproductive cycle, a long period of gonadal activity and a slight asynchronicity between the sexes. The spawning season comprised the period between April and July, with a clear spawning peak from May to June. The SL50 was reached at 56.4 mm in females and 54.6 mm in males. Although at present B. brandaris has no commercial value in Tunisia, it is predictable to become a fishery-exploited species in the near future. The present data, particularly the timing and duration of the spawning season and the size of individuals of both sexes at first sexual maturity, provide baseline information to propose the early adoption of fishery management measures, aimed at ensuring sustainable exploitation and long-term preservation of this alternative fishing resource, once commercial exploitation of this species commences.We are grateful to the technical staff of INSTM (Centre of Sfax) for their assistance during field surveys and laboratory procedures. Thanks are also due to Mr. Tarek Rebai (Medicine University, Sfax) and Mr. Mohamed Salah Romtdane (National Agronomic Institute, Tunis) for their valuable help during histological analyses. Paulo Vasconcelos is funded by a post-doctoral grant (SFRH/BPD/ 26348/2006) awarded by the Fundação para a Ciência e Tecnologia (FCT - Portugal). Finally, the authors acknowledge the valuable comments and suggestions provided by two anonymous reviewers and by the Editor-in-Chief of Mediterranean Marine Science.publishe

A combined (U-Th)/He and cosmogenic ^3He record of landscape armoring by biogeochemical iron cycling

(U‐Th)/He geochronology and cosmogenic ^3He in iron oxides reveal mineral precipitation ages as old as 55 Ma and exposure ages greater than 5 Ma for canga‐cemented plateaus in the Quadrilátero Ferrífero, Brazil, showing that lateritic profiles overlying banded iron‐formation (BIF) landscapes in tropical regions have a long history of surface exposure. The long‐term erosion history obtained from cosmogenic ^3He on BIF plateaus confirms that relic surfaces persist in the landscape for millions of years. Combined ^3He and (U‐Th)/He dating shows that cangas are preferentially goethite cemented by biogeochemical reactions in the subsurface. Importantly, pebbles of hematite‐magnetite in colluvia or shallow creeks draining the canga‐cemented plateaus record a much longer exposure history than in situ canga blocks, showing that even older duricrusts, now eroded, once blanketed these plateaus. Physically stable but biogeochemically dynamic, cangas armor the landscape by pervasive and recurrent iron cycling and cementation, slowing down the delivery of weathered BIF or friable hematite–magnetite ore to erosion

Discordant K-Ar and Young Exposure Dates for the Windjana sandstone, Kimberley, Gale Crater, Mars

K-Ar and noble gas surface exposure age measurements were carried out on the Windjana sandstone, Kimberley region, Gale Crater, Mars, by using the Sample Analysis at Mars instrument on the Curiosity rover. The sandstone is unusually rich in sanidine, as determined by CheMin X-ray diffraction, contributing to the high K_2O concentration of 3.09 ± 0.20 wt % measured by Alpha-Particle X-ray Spectrometer analysis. A sandstone aliquot heated to ~915°C yielded a K-Ar age of 627 ± 50 Ma. Reheating this aliquot yielded no additional Ar. A second aliquot heated in the same way yielded a much higher K-Ar age of 1710 ± 110 Ma. These data suggest incomplete Ar extraction from a rock with a K-Ar age older than 1710 Ma. Incomplete extraction at ~900°C is not surprising for a rock with a large fraction of K carried by Ar-retentive K-feldspar. Likely, variability in the exact temperature achieved by the sample from run to run, uncertainties in sample mass estimation, and possible mineral fractionation during transport and storage prior to analysis may contribute to these discrepant data. Cosmic ray exposure ages from ^3He and ^(21)Ne in the two aliquots are minimum values given the possibility of incomplete extraction. However, the general similarity between the ^3He (57 ± 49 and 18 ± 32 Ma, mean 30 Ma) and ^(21)Ne (2 ± 32 and 83 ± 24 Ma, mean 54 Ma) exposure ages provides no evidence for underextraction. The implied erosion rate at the Kimberley location is similar to that reported at the nearby Yellowknife Bay outcrop