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- Description:
- : Forests play a major role in the global carbon cycle. Previous studies on the capacity of forests to sequester atmospheric CO2 have mostly focused on carbon uptake, but the roles of carbon turnover time and its spatiotemporal changes remain poorly understood. Here, we used long-term inventory data (1955-2018) from 695 mature forest plots to quantify temporal trends in living vegetation carbon turnover time across tropical, temperate, and cold climate zones, and compared plot data to eight Earth system models (ESMs). Long-term plots consistently showed decreases in living vegetation carbon turnover time, likely driven by increased tree mortality across all major climate zones. Changes in living vegetation carbon turnover time were negatively correlated with CO2 enrichment in both forest plot data and ESM simulations. However, plot-based correlations between living vegetation carbon turnover time and climate drivers such as precipitation and temperature diverged from those of ESM simulations. Our analyses suggest that forest carbon sinks are likely to be constrained by a decrease in living vegetation carbon turnover time, and accurate projections of forest carbon sink dynamics will require an improved representation of tree mortality processes and their sensitivity to climate in ESMs.
- Subject:
- Forestry
- Creator:
- Anderegg, William R.L., Schraub, Marcus, Yu, Kailiang, Gessler, Arthur, Penuelas, Josep, Cailleret, Maxine, Peng, Changhui, Condit, Richard, Ferretti, Marco, Hubbell, Stephen P., Smith, William K., Sardans, Jordi, Levanic, Tom, Zhu, Kai, and Trugman, Anna T.
- Owner:
- KAILIANG YU
- Language:
- English
- Date Uploaded:
- 10/24/2019
- Date Modified:
- 12/09/2021
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/doi:10.7278/S50D-D656-FSP2
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- Description:
- Background: The objective of this study was to evaluate the effect of utilising larger lens cubes on phacoemulsification efficiency and chatter using 3 tips of different sizes and 2 ultrasound (US) approaches. Methods: This was an in vitro laboratory study conducted at the John A. Moran Eye Center Laboratory, University of Utah, Salt Lake City, UT, USA. Porcine lens nuclei were formalin-soaked for 2 hours, then divided into either 2.0 mm or 3.0 mm cubes. 30 degree bent 19 G, 20 G, and 21 G tips were used with a continuous torsional US system; and straight 19 G, 20 G, and 21 G tips were used with a micropulse longitudinal US system. Efficiency and chatter were determined. Results: Mean phacoemulsification removal time was higher with the 3.0 mm lens cube for all US variations and tip sizes. There were statistically significant differences between the 19 G and 21 G tips with micropulse longitudinal US using the 2.0 mm lens cube and the 3.0 mm lens cube, as well as with continuous transversal US using the 2.0 mm lens cube and the 3.0 mm lens cube. There was no significant difference between 19 G and 20 G tips with either lens cube size in either US approach. However, using both US approaches, trends were identical for both lens cube sizes in which the 19 G tips performed better than the 20 G and 21 G tips. Conclusion: Regardless of lens size, the 19 G needle was the most efficient, with the fewest outliers and smallest standard deviations.
- Subject:
- ophthalmology
- Creator:
- Barlow, William R., Bernhisel, Ashlie A., Zaugg, Brian, Olson, Randall J., Ramshekar, Aniket, Heczko, Joshua B., and Pettey, Jeff H.
- Depositor:
- Susan Schulman
- Owner:
- Jeff Pettey
- Based Near Label Tesim:
- Salt Lake City, Utah, United States
- Language:
- English
- Date Uploaded:
- 11/26/2019
- Date Modified:
- 12/09/2021
- Date Created:
- 20180201 - 20180204
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/doi:10.7278/S50D-ZTWP-VF00
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- Description:
- This project was a NSF-funded collaborative research project entitled: Collaborative Research: Deciphering Eolian Paleoenvironmental and Hydrodynamic records: Lower Jurassic Navajo Sandstone, Colorado Plateau, USA This was a multifaceted interdisciplinary study of the Lower Jurassic Navajo Sandstone (Ss)--a unique and distinctive unit in all of geologic history. This unit represents the largest known ancient desert (erg), and is typically classified as a record of a hyperarid environment. Furthermore, the Navajo Ss was deposited at a time when mammals were undergoing their first major diversification, and dinosaurs began to dominate the landscape in number and diversity. Our goal was to examine sedimentary features of the erg margin that recorded the active paleohydrology of the desert regime, and examine abundant trace- and body-fossil material to more fully document the structure and evolution of the biota in a variably arid landscape through Navajo Ss deposition. Field studies involved sedimentology and paleoecology. Laboratory studies involved isotope geochemistry of carbonate deposits, as well as thin section petrography.
- Creator:
- Chan, Marjorie A.
- Owner:
- BRIAN MCBRIDE
- Based Near Label Tesim:
- Moab, Utah, United States
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 12/09/2021
- Date Created:
- May 2015-May 2017
- Resource Type:
- Dataset
- Identifier:
- https://doi:10.7278/S50D-D7DX-GJG0
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- Description:
- The widely documented phenomenon of nighttime stomatal conductance (gsn) could lead to substantial water loss with no carbon gain, and thus it remains unclear whether nighttime stomatal conductance confers a functional advantage. Given that studies of gsn have focused on controlled environments or small numbers of species in natural environments, a broad phylogenetic and biogeographic context could provide insights into potential adaptive benefits of gsn. • We measured gsn on a diverse suite of species (n = 73) across various functional groups and climates-of-origin in a common garden to study the phylogenetic and biogeographic/climatic controls on gsn and further assessed the degree to which gsn co-varied with leaf functional traits and daytime gas exchange rates. • Closely related species were more similar in gsn than expected by chance. Herbaceous species had higher gsn than woody species. Species that typically grow in climates with lower mean annual precipitation – where the fitness cost of water loss should be the highest – generally had higher gsn. • Our results reveal the highest gsn rates in species from environments where neighboring plants compete most strongly for water, suggesting a possible role for the competitive advantage of gsn.
- Creator:
- Anderegg, William and Yu, Kailiang
- Owner:
- BRIAN MCBRIDE
- Language:
- English
- Date Uploaded:
- 07/10/2019
- Date Modified:
- 12/09/2021
- Date Created:
- 2018 May through August
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50D-E9J1-NYG0
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- Description:
- The dynamic properties of freestanding rock landforms are a function of fundamental material and mechanical parameters, facilitating non-invasive vibration-based structural assessment. Characterization of resonant frequencies, mode shapes, and damping ratios, however, can be challenging at culturally-sensitive geologic features, such as rock arches, where physical access is limited. Using sparse ambient vibration measurements, we describe three resonant modes between 1 and 40 Hz for 17 natural arches in Utah spanning a range of lengths from 3 – 88 m. Modal polarization data are evaluated to combine field observations with 3-D numerical models. We find outcrop-scale elastic moduli vary from 0.8 to 8.0 GPa, correlated with diagenetic processes, and identify low damping at all sites. Dense-array cross-correlation results from an additional arch validate predictions of simple bending modes and fixed boundary conditions. Our results establish use of sparse ambient resonance measurements for structural assessment and monitoring of arches and similar freestanding geologic features.
- Subject:
- geological engineering
- Creator:
- Finnegan, Riley, Moore, Jeffrey R, and Geimer, Paul R
- Owner:
- Paul Geimer
- Based Near Label Tesim:
- Utah, Utah, United States
- Language:
- English
- Date Uploaded:
- 01/13/2020
- Date Modified:
- 12/09/2021
- Date Created:
- 2015-2019
- Resource Type:
- Dataset
-
- Description:
- The Andes Cordillera, which runs the length of South America and rises up to 5,000 m MSL within 200 km of the Pacific coast, dramatically influences the distribution of winter precipitation and snowpack over Chile and Argentina. The study of orographic precipitation processes, particularly along the western slopes of the Andes, is important to improve forecasts of severe flooding and snowpack in a region that depends on snowmelt for water resources. While orographic effects have been investigated on synoptic scales in the Andes, the lack of operational radar coverage and high-elevation, long-term precipitation records have, before the present study, precluded an in-depth investigation into the mesoscale and microphysical processes that affect the distribution of precipitation in the region. This dataset was collected during the Chilean Orographic and Mesoscale Precipitation Study (ChOMPS), which, from May-October 2016, investigated the evolution of precipitation amounts, dropsize distribution, and the vertical profile of radar echoes along an east-west transect that stretched from the Pacific coast to the windward slope of the Andes. The transect, at ~36°S, was made up of a coastal site upstream of the coastal mountain range (Concepción), a central valley site (Chillán), and a mountain site (Las Trancas). Instrumentation along the transect included three vertically pointing Micro-Rain-Radars, two Parsivel Disdrometers, and several meteorological stations. The dataset documents the evolution of Doppler velocity and reflectivity profiles with inland extent during early, middle, and late storm sectors. Additionally, the transect provides a season-long record of the inland evolution of melting layer height as well as the prevalence and structure of shallow non-brightband rain and the characteristics of its inland penetration to the central valley. This dataset, the first of its kind in the Chilean Andes, provides unique insight into mesoscale and orographic precipitation processes that also have applicability to the west coast of the United States and other mountainous regions.
- Subject:
- Meteorology
- Creator:
- Campbell, Leah S., Minder, Justin, and Garreaud, Rene
- Contributor:
- Steenburgh, Jim, Rojas, Yazmina, Viscarra, Also, Montecinos, Aldo, Veloso, Daniel Sebastian, and Salazar, Diego Rivera
- Owner:
- Leahs Campbell
- Based Near Label Tesim:
- Chile, , Chile
- Language:
- English
- Date Uploaded:
- 05/16/2020
- Date Modified:
- 12/09/2021
- Date Created:
- May 15 2016 - October 7 2016
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/doi:10.7278/S50DJXEW0JH3
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- 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
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- 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
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- 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
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- 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