570 research outputs found

    SCR and GCR exposure ages of plagioclase grains from lunar soil

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    The concentrations of solar wind implanted Ar-36 in mineral grains extracted from lunar soils show that they were exposed to the solar wind on the lunar surface for an integrated time of 10E4 to 10E5 years. From the bulk soil 61501 plagioclase separates of 8 grain size ranges was prepared. The depletion of the implanted gases was achieved by etching aliquot samples of 4 grain sizes to various degrees. The experimental results pertinent to the present discussion are: The spallogenic Ne is, as in most plagioclases from lunar soils, affected by diffusive losses and of no use. The Ar-36 of solar wind origin amounts to (2030 + or - 100) x 10E-8 ccSTP/g in the 150 to 200 mm size fraction and shows that these grains were exposed to the solar wind for at least 10,000 years. The Ne-21/Ne-22 ratio of the spallogenic Ne is 0.75 + or - 0.01 and in very good agreement with the value of this ratio in a plagioclase separate from rock 76535. This rock has had a simple exposure history and its plagioclases have a chemical composition quite similar to those studied. In addition to the noble gases, the heavy particle tracks in an aliquot of the 150 to 200 mm plagioclase separate were investigated and found 92% of the grains to contain more than 10E8 tracks/sq cm. This corresponds to a mean track density of (5 + or - 1) x 10E8 tracks/sq cm. The exploration of the exposure history of the plagioclase separates from the soil 61501 do not contradict the model for the regolith dynamics but also fail to prove it

    Nitrogen and noble gases in the 71501 bulk soil and ilmenite as records of the solar wind exposure: Which is correct?

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    The N determination in mg sized mineral separates from lunar soils by static mass spectrometry is an experimental break-through likely to contribute to the deciphering of the records left in the mineral grains by the exposure to the solar wind. In this discussion some comparisons of the results of N and noble gas analyses of the 71501 bulk soil and an ilmenite separate thereof are focussed on. Conclusions from noble gas data obtained on mineral separates from some 20 soils are summarized in a companion paper and are also discussed herein

    Migration and health: Moving towards diversity-oriented public health monitoring at the Robert Koch Institute

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    Summarizing categories, such as migration background or history of migration, do not reflect the diversity and heterogeneity of the population living in Germany and their health. A differentiated description of the health situation of people with a history of migration should consider migrationrelated, social, and structural determinants of health as well as their interactions. The findings obtained in the 'Improving Health Monitoring in Migrant Populations (IMIRA)' projects will help to improve the inclusion of people with a history of migration in future studies as well as in the RKI panel. This will enable an adequate description of the health situation of people with a history of migration and therefore of the general population in Germany. In future studies, the health status of people who have not been well included in health surveys so far, such as people who are not listed at the registration office, should be monitored. For this purpose, continuous development of sampling and survey methods is necessary
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