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- Keyword:
- Climate, Clouds, Statistics, and Atmospheric Sciences
- Creator:
- Garrett, Tim
- Owner:
- BRIAN MCBRIDE
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 07/30/2019
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S5CV4FWW
2. Data for: Restitution Characteristics of His Bundle and Working Myocardium in Isolated Rabbit Hearts
- Description:
- The Purkinje system (PS) and the His bundle have been recently implicated as an important driver of the rapid activation rate after 1-2 minutes of ventricular fibrillation (VF). It is unknown whether activations during VF propagate through the His-Purkinje system to other portions of the the working myocardium (WM). Little is known about restitution characteristic differences between the His bundle and working myocardium at short cycle lengths. In this study, rabbit hearts (n=9) were isolated, Langendorff- perfused, and electromechanically uncoupled with blebbistatin (10 μM). Pacing pulses were delivered directly to the His bundle. By using standard glass microelectrodes, action potentials duration (APD) from the His bundle and WM were obtained simultaneously over a wide range of stimulation cycle lengths (CL). The global F-test indicated that the two restitution curves of the His bundle and the WM are statistically significantly different (P<0.05). Also, the APD of the His bundle was significantly shorter than that of WM throughout the whole pacing course (P<0.001). The CL at which alternans developed in the His bundle vs. the WM were shorter for the His bundle (134.2±13.1ms vs. 148.3±13.3ms, P<0.01) and 2:1 block developed at a shorter CL in the His bundle than in WM (130.0±10.0 vs. 145.6±14.2ms, P<0.01). The His bundle APD was significantly shorter than that of WM under both slow and rapid pacing rates, which suggest that there may be an excitable gap during VF and that the His bundle may conduct wavefronts from one bundle branch to the other at short cycle lengths and during VF.
- Keyword:
- ventricular fibrillation, action potential duration, cardiology, working myocardium, rabbit, restitution curve, alternans, His bundle, and microelectrode
- Creator:
- Ranjan, Ravi, Panitchob, Nuttanont, Huang, Shangwei, Huang, Liqun, Dosdall, Derek, and Hu, Nan
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Salt Lake City
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 07/30/2019
- Date Created:
- 20160321 to 20160525
- License:
- CCO – As the data author, you are choosing to place your data into the public domain.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50R9MJX
- Description:
- Supplementary material for a research paper submitted to the Journal of Applied Meteorology and Climatology. An animated gif and a readme file.
- Keyword:
- weather, flow, animination, Meteor Crater, katabatic flow, hydralic jump, potential temperature profile, IOP7, METCRAX, basin, and cold intrusions
- Creator:
- Adler, B., Lehner, M., Haiden, T., Kalthoff, N, Hoch, S. W., and Whiteman, C. David
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Meteor Crater
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 07/30/2019
- Date Created:
- October 10, 2017
- License:
- Public Domain – This data is free of copyright restrictions (e.g. government sponsored data).
- Resource Type:
- Image
- Identifier:
- https://doi.org/10.7278/S54J0C86
- Keyword:
- ophthalmology, retina, vitreous, adhesion, ocular, human, eye, peel test, and sheep
- Subject:
- Quantitative measurements of vitreoretinal adhesion in ovine and human subjects as a function of age and region
- Creator:
- Creveling, Christopher and Coats, Brittany
- Contributor:
- Colter, Jourdan
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Salt Lake City
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 07/30/2019
- Date Created:
- data collection completed June 1, 2017
- License:
- CC BY – Allows others to use and share your data, even commercially, with attribution.
- Resource Type:
- Image, Video, and Dataset
- Identifier:
- https://doi.org/10.7278/S5BK19H3
- Description:
- We consider a scenario where the small satellites of Pluto and Charon grew within a disk of debris from an impact between Charon and a trans-Neptunian Object (TNO). After Charon’s orbital motion boosts the debris into a disk-like structure, rapid orbital damping of meter-size or smaller objects is essential to prevent the subsequent re-accretion or dynamical ejection by the binary. From analytical estimates and simulations of disk evolution, we estimate an impactor radius of 30–100 km; smaller (larger) radii apply to an oblique (direct) impact. Although collisions between large TNOs and Charon are unlikely today, they were relatively common within the first 0.1–1 Gyr of the solar system. Compared to models where the small satellites agglomerate in the debris left over by the giant impact that produced the Pluto-Charon binary planet, satellite formation from a later impact on Charon avoids the destabilizing resonances that sweep past the satellites during the early orbital expansion of the binary.
- Keyword:
- Charon, Planets, Pluto-Charon binary planet, debris, simulations, Pluto , Satellites, trans-Neptunian Object, and TNO
- Subject:
- Astrophysics and Astronomy
- Creator:
- Bromley, Ben and Kenyon, Scott
- Owner:
- BENJAMIN BROMLEY
- Language:
- English
- Date Uploaded:
- 07/07/2020
- Date Modified:
- 07/10/2020
- Date Created:
- 201911 - 202004
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution.
- Identifier:
- https://doi.org/10.7278/S50D4AKFQZFC
- Description:
- Thin boundary layer Arctic mixed-phase clouds are generally thought to precipitate pristine and aggregate ice crystals. Here we present automated surface photographic measurements showing that only 35\% of precipitation particles exhibit negligible riming and that graupel particles $\geq1\,\rm{mm}$ in diameter commonly fall from clouds with liquid water paths less than $50\,\rm{g\,m^{-2}}$. A simple analytical formulation predicts that significant riming enhancement can occur in updrafts with speeds typical of Arctic clouds, and observations show that such conditions are favored by weak temperature inversions and strong radiative cooling at cloud top. However, numerical simulations suggest that a mean updraft speed of $0.75\,\rm{m\,s^{-1}}$ would need to be sustained for over one hour. Graupel can efficiently remove moisture and aerosols from the boundary layer. The causes and impacts of Arctic riming enhancement remain to be determined.
- Keyword:
- computational research, radiative transfer, microwave radiometer, liquid water path, graupel, Alaska, Atmospheric Radiation Measurement, water vaper, atmospheric science, arctic, and clouds
- Subject:
- Arctic research, Computational research, and Atmospheric sciences
- Creator:
- Garrett, Timothy J. and Fitch, Kyle E.
- Contributor:
- Gaustad, Krista, Shkurko, Konstantin , Maahn, Maximilian, and Talaei, Ahmad
- Owner:
- BRIAN MCBRIDE
- Language:
- English
- Date Uploaded:
- 06/04/2020
- Date Modified:
- 07/21/2020
- Date Created:
- Code creation dates from 20161208 to 20180609 and Processed between 20170627 and 20190320
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution. and Other – See README file for more information.
- Resource Type:
- Software or Program Code and Dataset
- Identifier:
- https://doi.org/10.7278/s50dva5jk2pd
- Description:
- We consider a scenario where the small satellites of Pluto and Charon grew within a disk of debris from an impact between Charon and a trans-Neptunian object (TNO). After Charon's orbital motion boosts the debris into a disk-like structure, rapid orbital damping of meter-sized or smaller objects is essential to prevent the subsequent reaccretion or dynamical ejection by the binary. From analytical estimates and simulations of disk evolution, we estimate an impactor radius of 30-100 km; smaller (larger) radii apply to an oblique (direct) impact. Although collisions between large TNOs and Charon are unlikely today, they were relatively common within the first 0.1-1 Gyr of the solar system. Compared to models where the small satellites agglomerate in the debris left over by the giant impact that produced the Pluto-Charon binary planet, satellite formation from a later impact on Charon avoids the destabilizing resonances that sweep past the satellites during the early orbital expansion of the binary.
- Keyword:
- collisions, planet dynamical evolution, Pluto, solar system, planet formation, dwarf planets, simulation, satellite formation, satellite dynamical evolution, Trans-Neptunian objects, and Charon
- Subject:
- Astrophysics
- Creator:
- Bromley, Benjamin and Kenyon, Scott
- Owner:
- BENJAMIN BROMLEY
- Date Uploaded:
- 08/03/2020
- Date Modified:
- 08/14/2020
- Date Created:
- 20191115 to 20200220
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50D5Q2MFDBT
- Description:
- This study investigates impacts of altering subgrid-scale mixing in “convection-permitting” km-scale horizontal grid spacing (∆h) simulations by applying either constant or stochastic multiplicative factors to the horizontal mixing coefficients within the Weather Research and Forecasting model. In quasi-idealized 1-km ∆h simulations of two observationally based squall line cases, constant enhanced mixing produces larger updraft cores that are more dilute at upper levels, weakens the cold pool, rear inflow jet, and front-to-rear flow of the squall line, and degrades the model’s effective resolution. Reducing mixing by a constant multiplicative factor has the opposite effect on all metrics. Completely turning off parameterized horizontal mixing produces bulk updraft statistics and squall line mesoscale structure closest to a LES “benchmark” among all 1-km simulations, although the updraft cores are too undilute. The stochastic mixing scheme, which applies a multiplicative factor to the mixing coefficients that varies stochastically in time and space, is employed at 0.5-, 1-, and 2-km ∆h. It generally reduces mid-level vertical velocities and enhances upper-level vertical velocities compared to simulations using the standard mixing scheme, with more substantial impacts at 1-km and 2-km ∆h compared to 0.5-km. The stochastic scheme also increases updraft dilution to better agree with the LES for one case, but has less impact on the other case. Stochastic mixing acts to weaken the cold pool but without a significant impact on squall line propagation. It also does not affect the model’s overall effective resolution unlike applying constant multiplicative factors to the mixing coefficients.
- Keyword:
- stochastic, stochastic mixing, WRF, squall line, simulation, Weather Research and Forecasting, and mixing
- Subject:
- Atmospheric Sciences
- Creator:
- Morrison, Hugh, Stanford, McKenna, and Varble, Adam
- Owner:
- MCKENNA STANFORD
- Language:
- English
- Date Uploaded:
- 08/17/2020
- Date Modified:
- 10/27/2020
- Date Created:
- 20190301 - 20200430
- License:
- Public Domain – This data is free of copyright restrictions (e.g. government sponsored data).
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DJNGQ6V67
- Description:
- Ground-based measurements of frozen precipitation are heavily influenced by interactions of surface winds with gauge-shield geometry. The Multi-Angle Snowflake Camera (MASC), which photographs hydrometeors in free-fall from three different angles while simultaneously measuring their fall speed, has been used in the field at multiple mid-latitude and polar locations both with and without wind shielding. Here we present an analysis of Arctic field observations — with and without a Belfort double Alter shield — and compare the results to computational fluid dynamics (CFD) simulations of the airflow and corresponding particle trajectories around the unshielded MASC. MASC-measured fall speeds compare well with Ka-band Atmospheric Radiation Measurement (ARM) Zenith Radar (KAZR) mean Doppler velocities only when winds are light (< 5 m/s) and the MASC is shielded. MASC-measured fall speeds that do not match KAZR measured velocities tend to fall below a threshold value that increases approximately linearly with wind speed but is generally < 0.5 m/s. For those events with wind speeds < 1.5 m/s, hydrometeors fall with an orientation angle mode of 12 degrees from the horizontal plane, and large, low-density aggregates are as much as five times more likely to be observed. Simulations in the absence of a wind shield show a separation of flow at the upstream side of the instrument, with an upward velocity component just above the aperture, which decreases the mean particle fall speed by 55% (74%) for a wind speed of 5 m/s (10 m/s). We conclude that accurate MASC observations of the microphysical, orientation, and fall speed characteristics of snow particles require shielding by a double wind fence and restriction of analysis to events where winds are light (< 5 m/s). Hydrometeors do not generally fall in still air, so adjustments to these properties' distributions within natural turbulence remain to be determined.
- Keyword:
- Winds, Snow, MATLAB, simulations, Multi-Angle Snowflake Camera, and Hydrometeors
- Subject:
- Atmospheric Science and Meteorology
- Creator:
- Talaei, Ahmad, Fitch, Kyle E., Garrett, Timothy J., and Hang, Chaoxun
- Owner:
- Language:
- English
- Date Uploaded:
- 07/20/2020
- Date Modified:
- 12/14/2020
- Date Created:
- 20120521 to 20200719
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution.
- Resource Type:
- Software or Program Code
- Identifier:
- https://doi.org/10.7278/S50DQTX9K7QY
- Description:
- Weather-related research often requires synthesizing vast amounts of data that need archival solutions that are both economical and viable during and past the lifetime of the project. Public cloud computing services (e.g., from Amazon, Microsoft, or Google) or private clouds managed by research institutions are providing object data storage systems appropriate for long-term archives of such large geophysical data sets. , History: This effort began in 2015 to illustrate the use of a private cloud object store developed by the Center for High Performance Computing (CHPC) at the University of Utah. We began archiving thousands of two-dimensional gridded fields (each one containing over 1.9 million values over the contiguous United States) from the High-Resolution Rapid Refresh (HRRR) data assimilation and forecast modeling system. The archive has been used for retrospective analyses of meteorological conditions during high-impact weather events, assessing the accuracy of the HRRR forecasts, and providing initial and boundary conditions for research simulations. The archive has been accessible interactively and through automated download procedures for researchers at other institutions that can be tailored by the user to extract individual two-dimensional grids from within the highly compressed files. Over a thousand users have voluntarily registered to use the HRRR archive at the University of Utah. Our archive has grown to over 130 Tbytes of model output but we no longer need to continue that effort since the GRIB2 files are available now via Google and AWS. As mentioned above, we now provide much of the same information in an alternative format that is appropriate particularly for machine-learning applications. , and Current Status: Our research group no longer needs to maintain archives of High Resolution Rapid Refresh (HRRR) model output at the University of Utah since complete publicly-accessible archives of HRRR model output are now available from the Google Cloud Platform and Amazon Web Services (AWS) as part of the NOAA Open Data Program. Google and AWS store the HRRR model output in GRIB2 format, a file type that efficiently stores hundreds of two-dimensional variable fields for a single valid time. Despite the highly compressible nature of GRIB2 files, they are often on the order of several hundred MB each, making high-volume input/output applications challenging due to the memory and compute resources needed to parse these files. With support from the Amazon Sustainability Data Initiative, our group is now creating and maintaining HRRR model output in an optimized format, Zarr, in a publicly-accessible S3 bucket- hrrrzarr. HRRR-Zarr contains sets for each model run of analysis and forecast files sectioned into 96 small chunks for every variable. The structure of the HRRR-Zarr files are designed to allow users the flexibility to access only the data they need through selecting subdomains and parameters of interest without the overhead that comes from accessing numerous GRIB2 files.
- Keyword:
- data assimilation, zarr, weather, forecasts, atmospheric science, analyses, High Resolution Rapid Refresh, and numerical weather prediction
- Subject:
- atmospheric science and numerical weather prediction
- Creator:
- Blaylock, Brian and Horel, John
- Contributor:
- Amazon Open Data Program, NOAA Environmental Modeling Center, University of Utah Center for High Performance Computing, and NOAA Earth Systems Research Laboratory
- Depositor:
- BRIAN MCBRIDE
- Owner:
- JOHN HOREL
- Language:
- binary and English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 04/15/2021
- Date Created:
- April 18, 2015 to present
- License:
- CC BY – Allows others to use and share your data, even commercially, with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://dx.doi.org/10.7278/S5JQ0Z5B