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Data associated with the publication: Jordan, A.K. et al. (2020) Strength of Linkages Between Dust and Circulation Over North Africa: results from a coupled modeling system with active dust. Journal of Geophysical Research-Atmospheres
No full textThis archive contains output from NASA Unified Weather Research and Forecasting (NU-WRF) model simulations reported in Jordan et al. (2020). The simulations are designed to examine hypothesized dust-atmosphere feedbacks in Northern Africa, in which dust in the atmosphere might act to modify the atmospheric conditions relevant to lofting of dust from the surface. To test this hypothesis, NU-WRF simulations were performed that coupled the WRF atmospheric model with the Goddard Chemistry Aerosols Radiation and Transport (GOCART) model. These simulations were performed with dust emissions on (“Dust On”) and dust emissions off (“Dust Off”), using a dust emission scheme that is responsive to surface soil moisture conditions and near-surface meteorology. Simulations were performed for the pre-rainy and rainy season (March-October) for fifteen simulation years (2002-2016). Model output was stored every six hours of simulation time. For archiving purposes, we have aggregated to monthly time-of-day averages, as this was the timescale of analysis reported in the paper
Data associated with publication “Assimilating GRACE into a Land Surface Model in the presence of an irrigation-induced groundwater trend”
No full textThe datasets include monthly time-varying greenness vegetation fraction and daily output of a set of four simulations performed with the Noah-Multiparameterization Land Surface Model v3.6 within NASA Land Information System. All simulations are conducted for the main GRACE data period (April 2002 to June 2017) at 0.125° spatial resolution forced by the North America Land Data Assimilation System-Phase 2 (NLDAS-2) meteorological forcing fields. Simulation outputs include surface water and energy fluxes and storages
Data associated the publication: Static polystyrene gate charge density modulation of dinaphthothienothiophene with tetrafluorotetracyanoquinodimethane layer doping: Evidence from conductivity and Seebeck coefficient measurements and correlations
No full textWe relate the static charging of organic field effect transistor (OFET) gate dielectric polymers, the resulting change in threshold voltage shift, and the modulation of thermoelectric properties of the transistor semiconductor. We utilize a bottom gate OFET structure with cross-linkable polystyrene and plain polystyrene (XLPS/PS) bilayer dielectrics and dinaphthothienothiophene (DNTT) organic molecular semiconductor with tetrafluorotetracyanoquinodimethane (F4TCNQ) doping layer. The conductivity and Seebeck coefficient are measured before and after charging. We find that the conductivity increases significantly, while the Seebeck coefficient decreases correspondingly in a trend of S ∝ ln(σ) after the dielectrics were negatively charged, resulting in an average of 5-fold increase in power factor at the maximum charging level. Additionally, temperature-dependent conductivity measurements show that the activation energy decreases with the increasing conductivity. We calculate the Seebeck coefficient based on the activation energy and find the result is consistent with the Mott mobility edge model. This work confirms the charging mechanism in our previous published work, including the location of static charges in the bulk of the dielectric, and demonstrates modulation and enhancement of the thermoelectric properties of organic thermoelectric materials by adjacent chargeable dielectrics without changing the molecular microstructure or applying external gate voltage during operation
Data associated with publication “Compositional Measurements of Saturn’s Upper Atmosphere and Rings from Cassini INMS” in the Journal of Geophysical Research: Planets
No full textThese data comprise the end-products of our analyses. This includes the cleaned Cassini INMS mass spectrum from orbits 288, 290, 291, 292, and 293 for m/z 1 to 20 amu. The inbound density profiles of H2, He, CH4, H2O, and NH3 as well as the averaged mixing ratios of CH4, H2O, and NH3 are also included
Data and code associated with the publication: Spatial distribution of people diagnosed with tuberculosis through routine and active case finding: a community-based study in Kampala, Uganda (STOMP-TB Study)
No full textStudy Overview and Population: This was a community-based study conducted in Kisugu, Wabigalo, and Bukasa parishes in Kampala, Uganda (an area of 2.2 km2 with an estimated population of 49,527) from May 2018 through December 2019. The study site consists of 37 contiguous zones; zones are the smallest standard administrative area unit used by the Uganda Bureau of Statistics, with a median size of 0.05km2 within the study area.
Case definition: A TB case was defined as any individual with a positive sputum smear or GeneXpert result, sputum culture positive for Mycobacterium tuberculosis, or documented initiation of TB treatment based on clinical judgment of pulmonary tuberculosis. In this analysis, we included only individuals who were age 15 years or older and residing within the study area; zone of residence was self-reported and verified using landmarks and Google Maps.
Case Detection and Enrollment: The study prospectively enrolled TB patients in two phases: a facility-based phase (May 2018-January 2019) and a community-based phase (February-December 2019). In the facility-based phase, we enrolled all consenting adult TB cases who lived in the study area and were passively identified through routine TB diagnostic services at four outpatient TB Diagnosis and Treatment Units located within the study area. In the community-based phase, we attempted to identify all prevalent TB cases in the community through a combination of passive and active case finding activities. Passive case detection continued at the four health facilities as described above
Data associated with publication "Biologically inspired catheter for endovascular sensing and navigation"
No full textMinimally invasive treatment of vascular disease demands dynamic navigation through complex blood vessel pathways and accurate placement of an interventional device, which has resulted in increased reliance on fluoroscopic guidance and commensurate radiation exposure to the patient and staff. Here we introduce a guidance system inspired by electric fish that incorporates measurements from a newly designed electrogenic sensory catheter with preoperative imaging to provide continuous feedback to guide vascular procedures without additional contrast injection, radiation, image registration, or external tracking. Electrodes near the catheter tip simultaneously create a weak electric field and measure the impedance, which changes with the internal geometry of the vessel as the catheter advances through the vasculature. The impedance time series is then mapped to a preoperative vessel model to determine the relative position of the catheter within the vessel tree. We present navigation in a synthetic vessel tree based on our mapping technique. Experiments in a porcine model demonstrated the sensor’s ability to detect cross-sectional area variation in vivo. These initial results demonstrate the capability and potential of this novel bioimpedance-based navigation technology as a non-fluoroscopic technique to augment existing imaging methods
Data and code associated with the publication “Feedbacks driving interdecadal variability in Southern Ocean convection in climate models: A coupled oscillator mechanism”
No full textThis dataset contains output from three coupled climate models used to look at the variability of Southern Ocean.
Model output generated using the ESM2Mc model described in Galbraith et al., Climate variability and radiocarbon in the CM2Mc Earth System Model , Journal of Climate., 24 , 4230-4254, https://doi.org/10.1175/2011JCLI3919.1 with several variants of the mixing coefficient. Runscript for the AREDI400 version of the model showing all parameters is provided as file 27. Files are divided into datasets followed by “.nc”, Matlab scripts (flat text) followed by a “.m”, and a flat text runscript file without a suffix
Data associated with the publication: A Synthesis of Quantitative Research on Programs For Struggling Readers in Elementary Schools
No full textThis article reviews research on the outcomes of diverse reading programs on the achievement of struggling readers in elementary schools. Sixty-five studies of 51 different programs met rigorous standards. Eighty-three percent were randomized experiments and 17% quasi-experiments. Outcomes were positive for one-to-one tutoring and were positive but not as large for one-to-small group tutoring. There were no differences in outcomes between teachers and teaching assistants as tutors. Whole-class approaches (mostly cooperative learning) and whole-class/whole-school approaches incorporating tutoring for struggling readers obtained outcomes for struggling readers as large as those found for all forms of tutoring, on average, and benefitted many more students. Technology-supported adaptive instruction did not have significant positive outcomes for struggling readers, however. In agreement with previous reviews, this synthesis found that substantial impacts can be obtained for struggling readers with interventions aligned within a response to intervention network
Data associated with publication “Variability in Locomotor Dynamics Reveals the Critical Role of Feedback in Task Control”
No full textThis project includes data from experiments conducted with weakly electric fish Eigenmannia virescens while tracking a moving a refuge. In this project, we studied the effect of sensory feedback on the variability of task performance. To examine this, we used data-driven system identification techniques to estimate transfer function models for the input—output behavioral response and the plant dynamics of the fish. We then, back-calculated associated sensorimotor controllers both in feedforward and feedback control topologies. Swapping controllers and plants across individuals in different control topologies allowed us to analyze the effect of sensory feedback on the variability of task performance. The project includes the data files for each experiment conducted with the fish
Data associated with the publication: Scaling global warming impacts on ocean ecosystems: Results from a suite of Earth System Models
No full textAn important technique used by climate modelers to isolate the impacts of increasing greenhouse gasses on Earth System processes is to simulate the impact of an abrupt increase in carbon dioxide. The spatial pattern of change provides a “fingerprint” that is generally much larger than natural variability. Insofar as the response to radiative forcing is linear (the impact of quadrupling CO2 is twice the impact of doubling CO2) this fingerprint can then be used to estimate the impact of historical greenhouse gas forcing. However the degree to which biogeochemical cycles respond linearly to radiative forcing has rarely been tested. In this paper, we evaluate which ocean biogeochemical fields are likely to respond linearly to changing radiative forcing, which ones do not, and where linearity breaks down. We also demonstrate that the representation of lateral mixing by mesoscale eddies, which varies significantly across climate models, plays an important role in modulating the breakdown of linearity. Globally integrated surface rates of biogeochemical cycling (primary productivity, particulate export) respond in a relatively linear fashion and can be moderately sensitive to mixing. By contrast, the habitability of the interior ocean (as determined by hypoxia and calcite supersaturation) behaves nonlinearly and is very sensitive to mixing. This is because the deep ocean, as well as certain regions in the surface ocean, are very sensitive to the magnitude of deep wintertime convection. The cessation of convection under global warming is strongly modulated by the representation of eddy mixing