{"dp_type": "Dataset", "free_text": "scanning electron microscopy"}
[{"awards": "1341612 Bowser, Samuel", "bounds_geometry": ["POINT(163.5117 -77.57623)"], "date_created": "Wed, 28 Nov 2018 00:00:00 GMT", "description": "This data set comprises scanning electron micrographs of Astrammina rara exposed to sub-lethal concentrations of lead and cadmium. Specimens were shucked (i.e., shells removed) and incubated with metal-free plastic beads for two weeks. Control (no Pb or Cd) and experimental (1 and 5 ug/ml Pb; 0.5 and 1 ug/ml Cd) specimens were prepared for SEM using fixation and dehydration in ethanol (i.e., no aldehydes) and were imaged uncoated at 3keV.", "east": 163.5117, "geometry": ["POINT(163.5117 -77.57623)"], "keywords": "Antarctica; Biota; Foraminifera; Heavy Metal Toxicity; Scanning Electron Microscop; Scanning Electron Microscope (SEM) Images; Scanning Electron Microscopy; Transantarctic Mountains", "locations": "Transantarctic Mountains; Antarctica", "north": -77.57623, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "persons": "Bowser, Samuel; Andreas, Amanda", "project_titles": "Assembling and Mining the Genomes of Giant Antarctic Foraminifera", "projects": [{"proj_uid": "p0000004", "repository": "USAP-DC", "title": "Assembling and Mining the Genomes of Giant Antarctic Foraminifera"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -77.57623, "title": "Scanning electron micrographs: Influence of heavy metal (Pb, Cd) exposure on shell morphogenesis in Astrammina rara, a giant agglutinated Antarctic foraminiferan protist.", "uid": "601138", "west": 163.5117}, {"awards": "1043690 Scherer, Reed", "bounds_geometry": ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"], "date_created": "Wed, 01 Jan 2014 00:00:00 GMT", "description": "Intellectual Merit: Diatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material.\nBroader impacts: This work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project.", "east": 180.0, "geometry": ["POINT(0 -89.999)"], "keywords": "Antarctica; Biota; Diatom; Marine Sediments; Oceans; Sediment Core; Southern Ocean", "locations": "Antarctica; Southern Ocean", "north": -60.0, "nsf_funding_programs": null, "persons": "Haji-Sheikh, Michael; Scherer, Reed Paul", "project_titles": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "projects": [{"proj_uid": "p0000360", "repository": "USAP-DC", "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -90.0, "title": "Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export", "uid": "600127", "west": -180.0}]
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| Dataset Title/Abstract/Map | NSF Award(s) | Date Created | PIs / Scientists | Project Links | Abstract | Bounds Geometry | Geometry | Selected | Visible |
|---|---|---|---|---|---|---|---|---|---|
|
Scanning electron micrographs: Influence of heavy metal (Pb, Cd) exposure on shell morphogenesis in Astrammina rara, a giant agglutinated Antarctic foraminiferan protist.
|
1341612 |
2018-11-28 | Bowser, Samuel; Andreas, Amanda |
Assembling and Mining the Genomes of Giant Antarctic Foraminifera |
This data set comprises scanning electron micrographs of Astrammina rara exposed to sub-lethal concentrations of lead and cadmium. Specimens were shucked (i.e., shells removed) and incubated with metal-free plastic beads for two weeks. Control (no Pb or Cd) and experimental (1 and 5 ug/ml Pb; 0.5 and 1 ug/ml Cd) specimens were prepared for SEM using fixation and dehydration in ethanol (i.e., no aldehydes) and were imaged uncoated at 3keV. | ["POINT(163.5117 -77.57623)"] | ["POINT(163.5117 -77.57623)"] | false | false |
|
Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export
|
1043690 |
2014-01-01 | Haji-Sheikh, Michael; Scherer, Reed Paul |
Southern Ocean Diatom Taphonomy and Paleoproductivity: A Laboratory Study of Silica Degradation and Export |
Intellectual Merit: Diatom abundance in sediment cores is typically used as a proxy for paleo primary productivity. This record is complicated by variable preservation, with most loss occurring in the water column via dissolution and zooplankton grazing. This study will investigate preservational biases via a series of controlled experiments to create proxies of original productivity based on morphological changes associated with diatom dissolution and fracture. The PIs will utilize fresh diatoms from culture. Specific objectives include: (1) Linking changes in diatom morphology to availability of dissolved silica and other physical and chemical parameters; (2) Documenting the dissolution process under controlled conditions; (3) Assessment of changes in morphology and diatom surface roughness with increased dissolution; (4) Documenting the physical effects of grazing and fecal pellet formation on diatom fragmentation and dissolution; and (5) Analyzing the impact of diatom dissolution on silica and carbon export. These objectives will be achieved by growing Southern Ocean diatom species in the laboratory under differing physical and chemical conditions; controlled serial dissolution experiments on cultured diatoms; analysis of the dissolution process by imaging frustules under scanning electron microscopy (SEM) and with micro-analysis of surface texture by atomic force microscopy (AFM); making the cultures available to krill and other live zooplankton crustaceans in order to analyze the specific effects of grazing and pelletization on diatom morphology; and comparing experimental results with natural plankton, sediment trap material, and selected Holocene, Pleistocene and Pliocene sediment core material. Broader impacts: This work will contribute to understanding of the use of diatom abundance as an indicator of paleoproductivity. The proposed experiments are multi-disciplinary in nature. Importantly, the project was designed, and the proposal largely written, by a Ph.D. candidate. The research proposed here will lead to peer-reviewed publications and provide a base for future studies over the course of an extremely promising scientific career. The project will also support an undergraduate research student at NIU. The PI is heavily involved in science outreach, including classroom visits, museum events and webinars related to evolution and climate change, and is active with NSF-funded outreach activities linked to the ANDRILL and WISSARD programs. He will continue these efforts with this project. | ["POLYGON((-180 -60,-144 -60,-108 -60,-72 -60,-36 -60,0 -60,36 -60,72 -60,108 -60,144 -60,180 -60,180 -63,180 -66,180 -69,180 -72,180 -75,180 -78,180 -81,180 -84,180 -87,180 -90,144 -90,108 -90,72 -90,36 -90,0 -90,-36 -90,-72 -90,-108 -90,-144 -90,-180 -90,-180 -87,-180 -84,-180 -81,-180 -78,-180 -75,-180 -72,-180 -69,-180 -66,-180 -63,-180 -60))"] | ["POINT(0 -89.999)"] | false | false |
