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![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Creator:
- Garrett, Tim
- Owner:
- BRIAN MCBRIDE
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 07/30/2019
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S5CV4FWW
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- 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.
- Subject:
- Astronomy and Astrophysics
- Creator:
- Kenyon, Scott and Bromley, Ben
- Owner:
- BENJAMIN BROMLEY
- Language:
- English
- Date Uploaded:
- 07/07/2020
- Date Modified:
- 07/10/2020
- Date Created:
- 201911 - 202004
- Identifier:
- https://doi.org/10.7278/S50D4AKFQZFC
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- 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.
- Subject:
- Atmospheric sciences, Computational research, and Arctic research
- Creator:
- Garrett, Timothy J. and Fitch, Kyle E.
- Contributor:
- Shkurko, Konstantin , Talaei, Ahmad, Gaustad, Krista, and Maahn, Maximilian
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Oliktok Point, Alaska, United States
- 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
- Resource Type:
- Software or Program Code and Dataset
- Identifier:
- https://doi.org/10.7278/s50dva5jk2pd
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- 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.
- Subject:
- Atmospheric Sciences
- Creator:
- Stanford, McKenna, Morrison, Hugh, and Varble, Adam
- Owner:
- MCKENNA STANFORD
- Language:
- English
- Date Uploaded:
- 08/17/2020
- Date Modified:
- 10/27/2020
- Date Created:
- 20190301 - 20200430
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DJNGQ6V67
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- 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.
- Subject:
- Meteorology and Atmospheric Science
- Creator:
- Talaei, Ahmad, Hang, Chaoxun, Fitch, Kyle E., and Garrett, Timothy J.
- Owner:
- Language:
- English
- Date Uploaded:
- 07/20/2020
- Date Modified:
- 12/14/2020
- Date Created:
- 20120521 to 20200719
- Resource Type:
- Software or Program Code
- Identifier:
- https://doi.org/10.7278/S50DQTX9K7QY
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- We analyzed 4,754 broadband seismic recordings of the SKS, SKKS, and SPdKS wavefield from 13 high quality events sampling the Samoa ultralow-velocity zone (ULVZ). We measured differential travel-times and amplitudes between the SKKS and SKS arrivals, which are highly sensitive to the emergence of the SPdKS seismic phase, which is in turn highly sensitive to lowermost mantle velocity perturbations such as generated by ULVZs. We modeled these data using a 2-D axi-symmetric waveform modeling approach and are able to explain these data with a single ULVZ. In order to predict both travel-time and amplitude perturbations we found that a large ULVZ length in the great circle arc direction on the order of 10° or larger is required. The large ULVZ length limits acceptable ULVZ elastic parameters. Here we find that δVS and δVP reductions from 20% to 22% and 15% to 17% respectively gives us the best fit, with a thickness of 26 km. Initial 3-D modeling efforts do not recover the extremes in the differential measurements, demonstrating that 3-D effects are important and must be considered in the future. However, the 3-D modeling is generally consistent with the velocity reductions recovered with the 2-D modeling. These velocity reductions are compatible with a compositional component to the ULVZ. Furthermore, geodynamic predictions for a compositional ULVZ that is moving predict a long linear shape similar to the shape of the Samoa ULVZ we confirm in this study. and This collection includes radial component displacement seismograms in the time window including the SKS, SKKS and SPdKS seismic arrivals. These data all interact with the Samoa ultra-low velocity zone at the core-mantle boundary. All data used in the study of Krier et al., 2021 (JGR) is included in this collection.
- Subject:
- Geology, seismology, and Geophysics
- Creator:
- Michael S. Thorne, Tarje Nissen-Meyer, Justin D. Krier, and Kuangdai Leng
- Owner:
- Michael Thorne
- Based Near Label Tesim:
- Tonga Trench, , Tonga
- Language:
- English
- Date Uploaded:
- 02/17/2021
- Date Modified:
- 12/09/2021
- Date Created:
- January 2019 to January 2020
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DT3X22GGB
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Using a suite of numerical calculations, we consider the long-term evolution of circumbinary debris from the Pluto--Charon giant impact. Initially, these solids have large eccentricity and pericenters near Charon's orbit. On time scales of 100--1000 yr, dynamical interactions with Pluto and Charon lead to the ejection of most solids from the system. As the dynamics moves particles away from the barycenter, collisional damping reduces the orbital eccentricity of many particles. These solids populate a circumbinary disk in the Pluto-Charon orbital plane; a large fraction of this material lies within a `satellite zone' that encompasses the orbits of Styx, Nix, Kerberos, and Hydra. Compared to the narrow rings generated from the debris of a collision between a trans-Neptunian object (TNO) and Charon, disks produced after the giant impact are much more extended and may be a less promising option for producing small circumbinary satellites.
- Subject:
- Astronomy
- Creator:
- Bromley, Benjamin and Kenyon, Scott
- Owner:
- BENJAMIN BROMLEY
- Language:
- English
- Date Uploaded:
- 02/03/2021
- Date Modified:
- 12/09/2021
- Date Created:
- 20191115 to 20200220
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DSSMBHHXN
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Objective: In 2018, the Network of the National Libraries of Medicine (NNLM) launched a national sponsorship program to support U.S. public library staff in completing the Medical Library Association’s (MLA) Consumer Health Information Specialization (CHIS). The primary objective of this research project was to determine if completion of the sponsored specialization was successful in improving public library staff ability to provide consumer health information and whether it resulted in new services, programming, or outreach activities at public libraries. Secondary objectives of this research were to determine motivation for and benefits of the specialization and to determine the impact on sponsorship on obtaining and continuing the specialization. Methods: To evaluate the sponsorship program, we developed and administered a 16-question online survey via REDCap in August 2019 to 224 public library staff that were sponsored during the first year of the program. We measured confidence and competence in providing consumer health information using questions aligned with the eight Core Competencies for Providing Consumer Health Information Services [1]. Additionally, the survey included questions about new consumer health information activities at public libraries, public library staff motivation to obtain the specialization, and whether it led to immediate career gains. To determine the overall value of the NNLM sponsorship, we measured whether funding made it more likely for participants to complete or continue the specialization. Results: Overall, 136 participants (61%) responded to the survey. Our findings indicated that the program was a success: over 80% of participants reported an increase in core consumer health competencies, with a statistically significant improvement in mean competency scores after completing the specialization. Ninety percent of participants have continued their engagement with NNLM, and over half offered new health information programs and services at their public library. All respondents indicated that completing the specialization met their expectations, but few reported immediate career gains. While over half of participants planned to renew the specialization or obtain the more advanced, Level II specialization, 72% indicated they would not continue without the NNLM sponsorship. Conclusion: Findings indicate that NNLM sponsorship of the CHIS specialization was successful in increasing the ability of public library staff to provide health information to their community. and This dataset represents the de-identified raw results of a 16-question, online survey (via REDCap) collected in August 2019 to 224 public library staff who were sponsored for a Consumer Health Information Specialization (CHIS). The purpose of the study was to determine whether the sponsorship program had an impact on public library staff to provide consumer health information.
- Subject:
- Interprofessional Relations, Information Services, Professional Competence, Librarians / education, Libraries, Libraries, Medical , Consumer Health Information, and Humans
- Creator:
- Lake, Erica, Wolfe, Susan M, Knapp, Molly , Spatz, Michele, and Kiscaden, Elizabeth
- Owner:
- Molly Knapp
- Based Near Label Tesim:
- United States, , United States
- Language:
- English
- Date Uploaded:
- 11/12/2020
- Date Modified:
- 02/05/2021
- Date Created:
- August 2019
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50D1DAY2QQQ
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- Background. Common cold viruses create significant health and financial burdens, and understanding key loci of transmission would help focus control strategies. This study (1) examines factors that influence when individuals transition from a negative to positive test (acquisition) or a positive to negative test (loss) of rhinovirus (HRV) and other respiratory tract viruses in 26 households followed weekly for one year, (2) investigates evidence for intrahousehold and interhousehold transmission and the characteristics of individuals implicated in transmission, and (3) builds data-based simulation models to identify factors that most strongly affect patterns of prevalence. Methods. We detected HRV, coronavirus, paramyxovirus, influenza and bocavirus with the FilmArray polymerase chain reaction (PCR) platform (BioFire Diagnostics, LLC). We used logistic regression to find covariates affecting acquisition or loss of HRV including demographic characteristics of individuals, their household, their current infection status, and prevalence within their household and across the population. We apply generalized linear mixed models to test robustness of results. Results. Acquisition of HRV was less probable in older individuals and those infected with a coronavirus, and higher with a higher proportion of other household members infected. Loss of HRV is reduced with a higher proportion of other household members infected. Within households, only children and symptomatic individuals show evidence for transmission, while between households only a higher number of infected older children (ages 5-19) increases the probability of acquisition. Coronaviruses, paramyxoviruses and bocavirus also show evidence of intrahousehold transmission. Simulations show that age-dependent susceptibility and transmission have the largest effects on mean HRV prevalence. Conclusions. Children are most likely to acquire and most likely to transmit HRV both within and between households, with infectiousness concentrated in symptomatic children. Simulations predict that the spread of HRV and other respiratory tract viruses can be reduced but not eliminated by practices within the home.
- Creator:
- Adler, Frederick R.
- Contributor:
- Ampofo, Krow, Pavia, Andrew, and Byington, Carrie L.
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Salt Lake City, Utah, United States
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 12/09/2021
- Date Created:
- August 2009 - August 2010
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S5XG9P97
![](/assets/work-ff055336041c3f7d310ad69109eda4a887b16ec501f35afc0a547c4adb97ee72.png)
- Description:
- This SAS program can be used to calculate Grocery Purchase Quality Index-2016 (GPQI-2016) total and component scores from food purchase data (dollars and cents) that have been summarized into the 29 categories of the USDA Food Plans. The code can be adapted to calculate GPQI-2016 scores for data that use a smaller number of categories.
- Creator:
- Brewster, Philip J, Guenther, Patricia M, and Hurdle, John F
- Contributor:
- Tran, Lethuy and Chidambaram, Valli
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- University of Utah, Utah, United States
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 12/09/2021
- Date Created:
- 2018
- Resource Type:
- Software or Program Code
- Identifier:
- https://doi.org/10.7278/S5HD7ST1