58 research outputs found
Global production and free access to Landsat-scale Evapotranspiration with EEFlux and eeMETRIC
EEFlux (Earth Engine Evapotranspiration Flux) is a version of the METRIC (mapping evapotranspiration at high resolution with internal calibration) application that operates on the Google Earth Engine (EE). EEFlux has a web-based interface and provides free public access to transform Landsat images into 30 m spatial evapotranspiration (ET) data for terrestrial land areas around the globe. EE holds the entire Landsat archive to power EEFlux along with NLDAS/CFSV2 gridded weather data for estimating reference ET. EEFlux is a part of the upcoming OpenET platform (https://openetdata.org/ ) that has leveraged nonprofit funding to provide ET information to all of the lower 48 states for free, as a means to foster water exchange between agriculture, cities and environment (Melton et al., 2020). The METRIC version in OpenET is named eeMETRIC, and includes cloud detection and time integration of ET snapshots into monthly ET estimates. EEFlux and eeMETRIC employ METRIC’s “mountain” algorithms for estimating aerodynamics and solar radiation in complex terrain. Calibration is automated and ET images are computed for download in seconds using EE’s large computational capacity
Bolide energy estimates from infrasonic measurements
Abstract. The acoustic amplitude-yield relationships, including formal errors, for a population of energetic (>0.05 kt) and well-observed bolide events have been investigated. Using various infrasonic signal measurements as a function of range, these data have been calibrated against optical yield estimates from satellite measurements. Correction for the presence of stratospheric winds has also been applied to the observations and is found to be small, suggesting that either scatter is dominated by other variations amongst the fireball population such as differing burst altitudes and greater or lesser amounts of fragmentation or the magnitude of the variability in the stratospheric winds, which can be comparable to or even exceed the strength of the winds themselves. Comparison to similar point source, ground-level nuclear and high explosive airwave data shows that bolide infrasound is consistently lower in amplitude. This downward shift relative to nuclear and HE data is interpreted as due in part to increased weak non-linearity during signal propagation from higher altitudes. This is a likely explanation, since mean estimates of the altitude of maximum energy deposition along the bolide trajectory was found to be between 20 and 30 km altitude for this fireball population
Orbital evolution of P\v{r}\'{i}bram and Neuschwanstein
The orbital evolution of the two meteorites P\v{r}\'{i}bram and
Neuschwanstein on almost identical orbits and also several thousand clones were
studied in the framework of the N-body problem for 5000 years into the past.
The meteorites moved on very similar orbits during the whole investigated
interval. We have also searched for photographic meteors and asteroids moving
on similar orbits. There were 5 meteors found in the IAU MDC database and 6
NEAs with currently similar orbits to P\v{r}\'{i}bram and Neuschwanstein.
However, only one meteor 161E1 and one asteroid 2002 QG46 had a similar orbital
evolution over the last 2000 years.Comment: 7 pages, 2 figures, 3 table
Error mitigation, optimization, and extrapolation on a trapped ion testbed
Current noisy intermediate-scale quantum (NISQ) trapped-ion devices are
subject to errors around 1% per gate for two-qubit gates. These errors
significantly impact the accuracy of calculations if left unchecked. A form of
error mitigation called Richardson extrapolation can reduce these errors
without incurring a qubit overhead. We demonstrate and optimize this method on
the Quantum Scientific Computing Open User Testbed (QSCOUT) trapped-ion device
to solve an electronic structure problem. We explore different methods for
integrating this error mitigation technique into the Variational Quantum
Eigensolver (VQE) optimization algorithm for calculating the ground state of
the HeH+ molecule at 0.8 Angstrom. We test two methods of scaling noise for
extrapolation: time-stretching the two-qubit gates and inserting two-qubit gate
identity operations into the ansatz circuit. We find the former fails to scale
the noise on our particular hardware. Scaling our noise with global gate
identity insertions and extrapolating only after a variational optimization
routine, we achieve an absolute relative error of 0.363% +- 1.06 compared to
the true ground state energy of HeH+. This corresponds to an absolute error of
0.01 +- 0.02 Hartree; outside chemical accuracy, but greatly improved over our
non error mitigated estimate. We ultimately find that the efficacy of this
error mitigation technique depends on choosing the right implementation for a
given device architecture and sampling budget.Comment: 16 pages, 11 figure
Evaluating psychometric properties of the Emotional Eating Scale Adapted for Children and Adolescents (EES-C) in a clinical sample of children seeking treatment for obesity: a case for the unidimensional model.
BackgroundThe Emotional Eating Scale - Adapted for Children and Adolescents (EES-C) assesses children's urge to eat in response to experiences of negative affect. Prior psychometric studies have demonstrated the high reliability, concurrent validity, and test-retest reliability of theoretically defined subconstructs among non-clinical samples of children and adolescents who were primarily healthy weight; however, no psychometric studies exist investigating the EES-C among clinical samples of children with overweight/obesity (OW/OB). Furthermore, studies conducted in different contexts have suggested a discordant number of subconstructs of emotions related to eating. The purpose of this study was to evaluate the validity of the EES-C in a clinical sample of children seeking weight-loss treatment.MethodUsing a hierarchical bi-factor approach, we evaluated the validity of the EES-C to measure a single general construct, a set of two separate correlated subconstructs, or a hierarchical arrangement of two constructs, and determined reliability in a clinical sample of treatment-seeking children with OW/OB aged 8-12 years (N = 147, mean age = 10.4 years.; mean BMI z = 2.0; female = 66%; Hispanic = 32%, White and other = 68%).ResultsComparison of factor-extraction methods suggested a single primary construct underlying EES-C in this clinical sample. The bi-factor indices provided clear evidence that most of the reliable variance in the total score (90.8 for bi-factor model with three grouping factors and 95.2 for bi-factor model with five grouping factors) was attributed to the general construct. After adjusting for relationships with the primary construct, remaining correlations among sets of items did not suggest additional reliable constructs.ConclusionResults suggest that the primary interpretive emphasis of the EES-C among treatment-seeking children with overweight or obesity should be placed on a single general construct, not on the 3- or 5- subconstructs as was previously suggested
OpenET : filling a critical data gap in water management for the western United States.
The lack of consistent, accurate information on evapotranspiration (ET) and consumptive use of water by irrigated agriculture is one of the most important data gaps for water managers in the western United States (U.S.) and other arid agricultural regions globally. The ability to easily access information on ET is central to improving water budgets across the West, advancing the use of data-driven irrigation management strategies, and expanding incentive-driven conservation programs. Recent advances in remote sensing of ET have led to the development of multiple approaches for field-scale ET mapping that have been used for local and regional water resource management applications by U.S. state and federal agencies. The OpenET project is a community-driven effort that is building upon these advances to develop an operational system for generating and distributing ET data at a field scale using an ensemble of six well-established satellite-based approaches for mapping ET. Key objectives of OpenET include: Increasing access to remotely sensed ET data through a web-based data explorer and data services; supporting the use of ET data for a range of water resource management applications; and development of use cases and training resources for agricultural producers and water resource managers. Here we describe the OpenET framework, including the models used in the ensemble, the satellite, meteorological, and ancillary data inputs to the system, and the OpenET data visualization and access tools. We also summarize an extensive intercomparison and accuracy assessment conducted using ground measurements of ET from 139 flux tower sites instrumented with open path eddy covariance systems. Results calculated for 24 cropland sites from Phase I of the intercomparison and accuracy assessment demonstrate strong agreement between the satellite-driven ET models and the flux tower ET data. For the six models that have been evaluated to date (ALEXI/DisALEXI, eeMETRIC, geeSEBAL, PT-JPL, SIMS, and SSEBop) and the ensemble mean, the weighted average mean absolute error (MAE) values across all sites range from 13.6 to 21.6 mm/month at a monthly timestep, and 0.74 to 1.07 mm/day at a daily timestep. At seasonal time scales, for all but one of the models the weighted mean total ET is within ±8% of both the ensemble mean and the weighted mean total ET calculated from the flux tower data. Overall, the ensemble mean performs as well as any individual model across nearly all accuracy statistics for croplands, though some individual models may perform better for specific sites and regions. We conclude with three brief use cases to illustrate current applications and benefits of increased access to ET data, and discuss key lessons learned from the development of OpenET
Polymorphisms in the selectin gene cluster are associated with fertility and survival time in a population of Holstein Friesian cows
Selectins are adhesion molecules, which mediate attachment between leucocytes and endothelium. They aid extravasation of leucocytes from blood into inflamed tissue during the mammary gland’s response to infection. Selectins are also involved in attachment of the conceptus to the endometrium and subsequent placental development. Poor fertility and udder health are major causes for culling dairy cows. The three identified bovine selectin genes SELP, SELL and SELE are located in a gene cluster. SELP is the most polymorphic of these genes. Several SNP in SELP and SELE are associated with human vascular disease, while SELP SNP rs6127 has been associated with recurrent pregnancy loss in women. This study describes the results of a gene association study for SNP in SELP (n = 5), SELL (n = 2) and SELE (n = 1) with fertility, milk production and longevity traits in a population of 337 Holstein Friesian dairy cows. Blood samples for PCR-RFLP were collected at 6 months of age and animals were monitored until either culling or 2,340 days from birth. Three SNP in SELPEx4-6 formed a haplotype block containing a Glu/Ala substitution at rs42312260. This region was associated with poor fertility and reduced survival times. SELPEx8 (rs378218397) coded for a Val475Met variant locus in the linking region between consensus repeats 4 and 5, which may influence glycosylation. The synonymous SNP rs110045112 in SELEEx14 deviated from Hardy Weinberg equilibrium. For both this SNP and rs378218397 there were too few AA homozygotes present in the population and AG heterozygotes had significantly worse fertility than GG homozygotes. Small changes in milk production associated with some SNP could not account for the reduced fertility and only SELPEx6 showed any association with somatic cell count. These results suggest that polymorphisms in SELP and SELE are associated with the likelihood of successful pregnancy, potentially through compromised implantation and placental development
Population, resources, and environment: Implications of human behavioral ecology for conservation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43481/1/11111_2005_Article_BF02207996.pd
Multi-station infrasonic observations of two large bolides: signal interpretation and implications for monitoring of atmospheric explosions
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