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Robert S. Webb Jonathan T. Overpeck David M. Anderson Bruce A. Bauer Mildred K. England Wendy S. Gross E. Ann Meyers Michael M. Worobec 《Journal of Paleolimnology》1993,9(1):69-75
Conclusion The World Data Center-A for Paleoclimatology, located in the NOAA/NGDC Paleoclimatology Program, is committed to providing the scientific community with easy access to all paleoenvironmental data. Efforts to make archived data readily available include international coordination of data acquisition, management, and distribution, sponsoring workshops and data cooperatives to facilitate the compilation of important data sets, development of a browse and visualization software package (PaleoVu), and dispersal of archived data on magnetic media or over ANONYMOUS FTP/INTERNET. The program publishes a semi-annual newsletter that highlights latest developments and accomplishments in the area of paleoenvironmental data for global change research. Contributions to the newsletter are welcome from researchers describing their efforts to coordinate the free flow of paleoclimate data throughout the international scientific community.For information on the program or to be added to the mailing list contact Mrs Mildred England (phone: 303-497-6227; Fax: 303 497-6513; e-mail: MKE@mail.ngdc.noaa.gov), NOAA National Geophysical Data Center, Paleoclimatology Program/World Data Center-A for Paleoclimatology, 325 Broadway, E/GC Boulder, CO 80303 USA 相似文献
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Mildred Berman 《The Professional geographer》1974,26(1):8-11
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Mildred Berman 《The Professional geographer》1980,32(2):199-204
Millicent Todd Bingham was the first and only woman to earn a Ph.D. in the Department of Geology and Geography at Harvard. A talented linguist, she published in the classic tradition of the French school of human geography. Her professional geographic career came to a halt when she elected to edit the poems and letters of Emily Dickinson, work originally begun by her mother, Mabel Loomis Todd. Bingham's efforts resulted in the publication of several books and articles fundamental to the Dickinson scholarship. She credits her geographic training for much of her literary success. 相似文献
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Aaron S. BURTON Jamie E. ELSILA Michael P. CALLAHAN Mildred G. MARTIN Daniel P. GLAVIN Natasha M. JOHNSON Jason P. DWORKIN 《Meteoritics & planetary science》2012,47(3):374-386
Abstract– Asteroids and their fragments have impacted the Earth for the last 4.5 Gyr. Carbonaceous meteorites are known to contain a wealth of indigenous organic molecules, including amino acids, which suggests that these meteorites could have been an important source of prebiotic organic material during the origins of life on Earth and possibly elsewhere. We report the detection of extraterrestrial amino acids in thermally altered type 3 CV and CO carbonaceous chondrites and ureilites recovered from Antarctica. The amino acid concentrations of the thirteen Antarctic meteorites ranged from 300 to 3200 parts‐per‐billion (ppb), generally much less abundant than in amino acid‐rich CI, CM, and CR carbonaceous chondrites that experienced much lower temperature aqueous alteration on their parent bodies. In contrast to low‐temperature aqueously altered meteorites that show complete structural diversity in amino acids formed predominantly by Strecker–cyanohydrin synthesis, the thermally altered meteorites studied here are dominated by small, straight‐chain, amine terminal (n‐ω‐amino) amino acids that are not consistent with Strecker formation. The carbon isotopic ratios of two extraterrestrial n‐ω‐amino acids measured in one of the CV chondrites (δ13C approximately ?25‰) are consistent with 13C‐depletions observed previously in hydrocarbons produced by Fischer‐Tropsch type reactions. The predominance of n‐ω‐amino acid isomers in thermally altered meteorites hints at cosmochemical mechanisms for the preferential formation and preservation of a small subset of the possible amino acids. 相似文献
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Scott A. SANDFORD Saša BAJT Simon J. CLEMETT George D. CODY George COOPER Bradley T. DEGREGORIO Vanessa
De VERA Jason P. DWORKIN Jamie E. ELSILA George J. FLYNN Daniel P. GLAVIN Antonio LANZIROTTI Thomas LIMERO Mildred P. MARTIN Christopher J. SNEAD Maegan K. SPENCER Thomas STEPHAN Andrew WESTPHAL Sue WIRICK Richard N. ZARE Michael E. ZOLENSKY 《Meteoritics & planetary science》2010,45(3):406-433
Abstract– Numerous potential sources of organic contaminants could have greatly complicated the interpretation of the organic portions of the samples returned from comet 81P/Wild 2 by the Stardust spacecraft. Measures were taken to control and assess potential organic (and other) contaminants during the design, construction, and flight of the spacecraft, and during and after recovery of the sample return capsule. Studies of controls and the returned samples suggest that many of these potential sources did not contribute any significant material to the collectors. In particular, contamination from soils at the recovery site and materials associated with the ablation of the heatshield do not appear to be significant problems. The largest source of concern is associated with the C present in the original aerogel. The relative abundance of this carbon can vary between aerogel tiles and even within individual tiles. This C was fortunately not distributed among a complex mixture of organics, but was instead largely present in a few simple forms (mostly as Si‐CH3 groups). In most cases, the signature of returned cometary organics can be readily distinguished from contaminants through their different compositions, nonterrestrial isotopic ratios, and/or association with other cometary materials. However, some conversion of the carbon indigenous to the flight aerogel appears to have happened during particle impact, and some open issues remain regarding how this C may be processed into new forms during the hypervelocity impact collection of the comet dust. 相似文献
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Whilst the UK is planned to have a census in 2021, it may well be the last and there is official acknowledgement that the country’s statistical system should be enhanced by greater use of administrative data. Thus, there is a pressing need to understand whether alternative data sources are fit for social science purposes. This study assesses the potential of utilizing administrative statistics for investigating the relationships between health and socioeconomic distributions for small areas; a type of study regularly carried out using census data. Pairs of administrative measures of health and deprivation indicator variables are compared with census equivalents for lower super output area geographies in England in 2001. The administrative datasets are then used to derive health measures and deprivation indexes for the time points 2001, 2006 and 2010. Inequalities in health are then analysed using administrative data derived area measures with health found to be poorer in areas with socioeconomic disadvantage. Overall, the administrative datasets used here reveal very similar patterns of health and deprivation to the decennial census suggesting they are viable alternatives and have great potential to enhance the country’s statistical system given their availability outside census years. 相似文献
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Aromatic hydrocarbons account for a significant portion of the organic matter in carbonaceous chondrite meteorites, as a component of both the low molecular weight, solvent-extractable compounds and the insoluble organic macromolecular material. Previous work has suggested that the aromatic compounds in carbonaceous chondrites may have originated in the radiation-processed icy mantles of interstellar dust grains. Here we report new studies of the organic residue made from benzene irradiated at 19 K by 0.8 MeV protons. Polyphenyls with up to four rings were unambiguously identified in the residue by gas chromatography–mass spectrometry. Atmospheric pressure photoionization Fourier transform mass spectrometry was used to determine molecular composition, and accurate mass measurements suggested the presence of polyphenyls, partially hydrogenated polyphenyls, and other complex aromatic compounds. The profile of low molecular weight compounds in the residue compared well with extracts from the Murchison and Orgueil meteorites. These results are consistent with the possibility that solid phase radiation chemistry of benzene produced some of the complex aromatics found in meteorites. 相似文献
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