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COLDEX Unfocused Airborne VHF Radar Transects: 2023-2024 South Pole Field Season
No full textThese transect organized radargrams were collected as part of the Center for Oldest Ice Exploration (COLDEX) Science and Technology Center (https://www.coldex.org) in the 2023/24 (CXA2) airborne reconnaissance field season. The raw 3 TB data is deposited at the USAP data center at https://doi.org/10.15784/601768. Flight organized data with additional processing by the University of Kansas to remove electromagnetic interference can be found at the Open Polar Radar server (https://www.openpolarradar.org). The science goal was to characterize the ice sheet between Antarctica's Dome A and Amundsen Scott South Pole Station, to locate sites of interest for the drilling of an ice core with ages spanning the mid-Pleistocene. The radar was deployed on Balser C-FMKB, and flown at ranges of up to 800 km from South Pole Station at velocities of 90 m/s and typical altitude above ground of 600 m. Other instruments included a UHF array system provided by the University of Kansas, a gravity meter, a magnetometer, a laser altimeter, and multiple global navigation satellite systems receivers. The radar data is used for finding ice thickness, bed character, englacial structure and surface assessment.
Dataset organization
Transects are provided a P/S/T nomenclature, organized by the Project they are flying in, the acquisition System (typically named after the aircraft) and the Transect within the Project.
Transects were collected in preplanned systems with the following parameters:
CLX radials (CLX/MKB##/R###), attempting to emulate flow lines from Dome A and radiating (in the EPSG:3031 polar stereographic projection) from easting 965 km northing 385 km, with a separation of 0.25 degrees.
CLX corridor (CLX/MKB##/X###) rotated from the EPSG:3031 polar stereographic projection at -150 degrees and separated by 10 km in the Y direction and 3.75 km in the X direction
CLX2 corridor (CLX2/MKB##/X###) rotated from the EPSG:3031 polar stereographic projection at -150 degrees and separated by 2.5 km in its Y direction and 2.5 km in its X direction
NPXE radials (NPXE/MKB##/R####) primarily designed to survey the Upper Byrd Glacier Catchment, constitute spokes radiating from South Pole separated by 2 degrees, in the EPSG:3031 polar stereographic projection
Untargeted transit lines used the name of the expedition (CXA2) as the project, and used the flight and the increment within the flight to name the Transect (eg (CXA2/MKB2n/F10T02a).
Processing
These data represent range compressed VHF radargrams as collected and analyzed in the field. The data are from the MARFA radar system, a 60 MHz ice penetrating radar system that has operated in several different guises over the years. MARFA operates with a 1 microsecond chirp with a design bandwidth of 15 MHz, allowing for ~8 meter range resolution. The record rate after onboard stacking is 200 Hz. High and low gain channels are collected from antennas on each side of the aircraft. In ground processing, the data were stacked 10x coherently to reduce range delayed incoherent surface scattering, and then stacked 5 times incoherently to improve image quality. In this preliminary processing, the effective resolution of deep scattering is several hundred meters due to range ambiguities at depth.
Data format These data collection represents georeferenced, time registered instrument measurements (L1B data) converted to SI units. The data format are netCDF3 files, following the formats used for NASA/AAD/UTIG's ICECAP/OIB project at NASA's NSIDC DAAC (10.5067/0I7PFBVQOGO5). Metadata fields can be accessed using the open source ncdump tool, or c, python or matlab modules. A Keyhole Metadata Language (KML) file with geolocation for all transects is also provided. See https://www.loc.gov/preservation/digital/formats/fdd/fdd000330.shtml for resources on NetCDF-3, and https://nsidc.org/data/IR2HI1B/versions/1 for a description of the similar OIB dataset.
Acknowledgements This work was supported by the Center for Oldest Ice Exploration, an NSF Science and Technology Center (NSF 2019719). We thank the NSF Office of Polar Programs, the NSF Office of Integrative Activities, and Oregon State University for financial and infrastructure support, and the NSF Antarctic Infrastructure and Logistics Program, and the Antarctic Support Contractor for logistical support. Additional support was provided by the G. Unger Vetlesen Foundation. <p
Pintura del pueblo Tepatepec contra Manuel de Olvera, circa 1570-1572
No full textAn Indigenous scribe lists the instances in which they felt Mixquiahuala’s corregidor, the district’s royal administrator and judge, defrauded them. The text describes a series of events involving Manuel de Olvera, a former corregidor, and various financial transactions and conflicts with individuals and authorities in Mixquiahuala and Tepatepec. It includes allegations of misappropriation of funds, mistreatment of individuals, and failure to fulfill promises or obligations. The document also mentions specific amounts of money, sheep, and other items involved in these transactions and conflicts. The community appended this claim to a legal case brought forth in an ecclesiastical court by Mixquiahuala’s parish priest, Juan de Cabrera, who claimed Olvera was keeping the Indigenous from attending his religious services and not paying his clerical salary. —— En este documento, un escribano indígena enumera las instancias en las que el pueblo sintió que el corregidor de Mixquiahuala, el administrador real y juez del distrito, los defraudó. El texto describe una serie de eventos que involucran a Manuel de Olvera, un corregidor previo, y varias transacciones financieras y conflictos con individuos y autoridades en Mixquiahuala y Tepatepec. Incluye acusaciones de malversación de fondos, maltrato a personas y falta de cumplimiento de promesas u obligaciones. El documento también menciona cantidades específicas de dinero, ovejas y otros elementos involucrados en estas transacciones y conflictos. La comunidad anexó este reclamo a un caso judicial presentado en un tribunal eclesiástico por el párroco de Mixquiahuala, Juan de Cabrera, quien afirmó que Olvera impedía que los nativos asistieran a sus servicios religiosos y no pagaba su salario de clérigo. 1 f. (2 p.
X-ray CT Scans of Sphere Phantom
No full textX-ray CT scans of phantom with 208 19-mm (3/4") diameter glass spheres in hexagonal pattern, used for evaluating 3D data processing.
Voxel Size is variable; data provided with varying degrees of down-sampling. Data reduced to 8-bit TIFF from 16-bit original.
Please acknowledge The University of Texas High-Resolution X-ray CT Facility (UTCT) when using this data
Potassium XANES datasets for potassium sorption to Al and Si oxides
No full textHere you can find the raw data for potassium XANES spectra used in Coyle et al., 2023 and Pham et al., 2022. These data may be used freely by anyone, but any resulting publications that use these data must cite Coyle et al., 2023 and/or Pham et al., 2022 in their reference sections. Data files are in the Athena (Demeter package) format for X-ray absorption spectroscopy. Best regards, Matthew G. Siebecker, Dept of Plant and Soil Science, Texas Tech University. (2024-03-22
Code
No full textThis file contains Matlab codes used to reconstruct and process the zebrafish embryo data.
Using "main_data_sequence.m", the FOV selected by the user will be divided into 9 patches and reconstructed sequentially. The example patch reconstruction results can be found in "Reconstruction results"->"FOV_01"->"mat".
"makeTotalFOV.m" is used to stitch the patch reconstructions. The example total FOV reconstruction results can be found in "Reconstruction results"->"FOV_01"->"result_total.mat".
"stitch3D.m" is used to stitch the FOVs together. The example total FOV reconstruction results can be found in "Reconstruction results"->"recon_multiFOVs.mat"
mouse_DG_scRNA-seq
No full textR objects and scripts for all analysis included in https://doi.org/10.1101/2023.12.31.57378
