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Invoice from The Macovich Collection for NWA 5790 meteorites
No full textInvoice from The Macovich Collection to Oscar Monnig for purchase of NWA 5790 meteorite
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Northwest Africa 5790. Top Sequence of the Nakhlite Pile
Get PDFNWA 5790 is a recently discovered nakhlite. Its mineralogy, petrology and geochemistry suggest that it is the topmost sequence of the nakhlite lava pile
Sm-Nd Isotopic Studies of Two Nakhlites, NWA 5790 and Nakhla
Get PDFNWA 5790 is a Martian meteorite recently found in the Mauritania part of the Saharan desert and is classified as a nakhlite, containing a small amount of interstitial plagioclase. Unlike other Martian meteorites ( e.g., shergottites), nakhlites have been only moderately shocked and their original igneous textures are still well-preserved. In this report, we present Sm-Nd isotopic data for NWA 5790 and Nakhla, a rare "fall" nakhlite, correlate their ages with those of other nakhlites and discuss their petrogenesis
Linked collectors and determiners for: Manzuma gen. nov., a new aelurilline genus of jumping spiders (Araneae, Salticidae).
No full textNatural history specimen data linked to collectors and determiners held within, "Manzuma gen. nov., a new aelurilline genus of jumping spiders (Araneae, Salticidae)". Claims or attributions were made on Bionomia by volunteer Scribes, <a href="http://bionomia.net/dataset/c80bd38d-5790-4da4-9008-59055a4add8f">https://bionomia.net/dataset/c80bd38d-5790-4da4-9008-59055a4add8f</a> using specimen data from the dataset aggregated by the Global Biodiversity Information Facility, <a href="https://gbif.org/dataset/c80bd38d-5790-4da4-9008-59055a4add8f">https://gbif.org/dataset/c80bd38d-5790-4da4-9008-59055a4add8f</a>. Formatted as a Frictionless Data package
Greenhouse Gas Emissions in Rosemount: Analysis and Recommendations
No full textPresentation and memo (report) completed by students enrolled in PA 4790/5790: Sustainable Infrastructure and Cities, taught by Anu Ramaswami in spring 2015.This project was completed as part of a year-long partnership between the City of Rosemount and the University of Minnesota’s Resilient Communities Project (http://www.rcp.umn.edu). The City of Rosemount is actively working to minimize its contribution to climate change by reducing greenhouse gas emissions. The goal of this project was to develop a climate action plan for the City of Rosemount that identifies specific strategies for reducing greenhouse gas emissions throughout the community. In collaboration with city project lead Jason Lindahl, a planner for the City of Rosemount, a team of students in PA 4790/5790: Sustainable Infrastructure and Cities analyzed local data and developed recommendations to reduce carbon emissions in the City of Rosemount for the energy, transportation, water, and food sectors, in addition to general recommendations. A final presentation and memo to the City of Rosemount from the project are available.This project was supported by the Resilient Communities Project (RCP), a program at the University of Minnesota that convenes the wide-ranging expertise of U of M faculty and students to address strategic local projects that advance community resilience and sustainability. RCP is a program of the Center for Urban and Regional Affairs (CURA). More information at http://www.rcp.umn.eduStudents enrolled in PA 4790/5790. (2015). Greenhouse Gas Emissions in Rosemount: Analysis and Recommendations. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/180463
Northwest Africa 5790: Revisiting Nakhlite Petrogenesis
No full textInternational audienceNorthwest Africa 5790, the latest nakhlite find, is composed of 58 vol.% augite, 6% olivine and 36% vitrophyric intercumulus material. Its petrology is comparable to previously discovered nakhlites but with key differences: (1) Augite cores display an unusual zoning between Mg# 54 and 60; (2) Olivine macrocrysts have a primary Fe-rich core composition (Mg#= 35); (3) the modal proportion of mesostasis is the highest ever described in a nakhlite; (4) It is the most magnetite-rich nakhlite, together with MIL 03346, and exhibits the least anisotropic fabric. Complex primary zoning in cumulus augite indicates resorption due to complex processes such as remobilization of former cumulates in a new magma batch. Textural relationships indicate unambiguously that olivine was growing around resorbed augite, and that olivine growth was continuous while pyroxene growth resumed at a final stage. Olivine core compositions (Mg#= 35) are out of equilibrium with the augite core compositions (Mg# 60-63) and with the previously inferred nakhlite parental magma (Mg#= 29). The presence of oscillatory zoning in olivine and augite precludes subsolidus diffusion that could have modified olivine compositions. NWA 5790 evidences at least two magma batches before eruption, with the implication that melt in equilibrium with augite cores was never in contact with olivine. Iddingsite is absent
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The Northwest Africa (NWA) 5790 meteorite: a mesostasis-rich nakhlite with little or no Martian aqueous alteration
Get PDFNorthwest Africa (NWA) 5790 is the most recently discovered member of the nakhlite group. Its mineralogy differs from the other nakhlites with a high abundance mesostasis (38.1 ± 3.6 vol%) and scarcity of olivine (4.0 ± 2.2 vol%). Furthermore, zoning of augite phenocrysts, and other petrographic and chemical characteristics suggest that NWA 5790 samples the chilled margin of its parent lava flow/sill. NWA 5790 contains calcite and rare clay minerals that are evidence for its exposure to liquid water. The calcite forms a cement to coatings of dust on the outer surface of the find and extends into the interior of the meteorite within veins. The presence of microbial remains within the coating confirms that the dust and its carbonate cement are terrestrial in origin, consistent with the carbon and oxygen isotope composition of the calcite. The clay minerals are finely crystalline and comprise ~0.003 vol% of the meteorite. δD values of the clay minerals range from −212 ± 109‰ to −96 ± 132‰, and cannot be used to distinguish between a terrestrial or Martian origin. As petrographic results are also not definitive, we conclude that secondary minerals produced by Martian groundwaters are at best very rare within NWA 5790. The meteorite has therefore sampled a region of the lava flow/sill with little or no exposure to the aqueous solutions that altered other nakhlites. This isolation could relate to the scarcity of olivine in NWA 5790 because dissolution of olivine in other nakhlites by Martian groundwaters enhanced their porosity and permeability, and provided solutes for secondary minerals
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