Donald R. Johnson

The Guiana current: a fast-lane to the Caribbean for holopelagic Sargassum contaminated in arsenic and cadmium

Tristan Gobert, Solène Connan, Donald R. Johnson, Matthieu Waeles

To date, little key information about inorganic arsenic (iAs) and cadmium (Cd) has been promulgated to help manage the massive influxes of pelagic Sargassum that have inundated the Caribbean coasts since 2011 and are causing significant environmental, health and economic impacts. In …

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Does Gait Assistance Modulate Reflex Excitability in Those with Spasticity? A Preliminary Study

Ricardo Siu, D. Lorenz, J.‐P. Stahl, Mark Waschak et autres

Stiff-Knee gait (SKG) is a common post-stroke impairment, marked by insufficient knee flexion during the swing phase, which reduces toe clearance, increases fall risk, and requires compensatory movements that can have adverse biomechanical effects. To address muscle weakness and paresis in SKG, …

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Identifying coronal sources of L1 solar wind disturbances using the Fisk heliospheric magnetic field and potential field extrapolations during three solar minima

P. J. Steyn, Donald R. Johnson, G. J. J. Botha, Stéphane Régnier

The solar minima between solar cycles 22-23, 23-24 and 24-25 are the best observed minima on record. In situ solar wind and interplanetary magnetic field measurements by the WIND and ACE spacecraft at L1 with one-hour cadence are explored using wavelet analyses …

NOAA's National Water Model: Advancing operational hydrology through continental‐scale modeling

Brian A. Cosgrove, David Gochis, Trey Flowers, Aubrey L. Dugger et autres

Abstract The National Weather Service (NWS) Office of Water Prediction (OWP), in conjunction with the National Center for Atmospheric Research and the NWS National Centers for Environmental Prediction (NCEP) implemented version 2.1 of the National Water Model (NWM) into operations in April …

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Tungsten Electrodeposition

Kendrich O. Hatfield, USDOE National Nuclear Security Administration (NNSA), Donald R. Johnson, Michael McBride

Tungsten is a refractory metal with a very high melting point (3422 °C), hardness (7.5 on Mohs hardness scale), and chemical resistance, making it useful in applications with extreme conditions. Electrodeposition is an attractive technique for coating metals because of its scalability …

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National Water Model V2.1 Validation Period Streamflow Output Data

Brian A. Cosgrove, David Gochis, Trey Flowers, Aubrey L. Dugger et autres

This resource contains data which underpins the National Water Model (NWM) version 2.1 analyses presented in the article "NOAA's National Water Model: Advancing Operational Hydrology Through Continental-Scale Modeling" appearing in the Journal of the American Water Resources Association. Please see the readme.txt …

Seasonal variation in morphotype composition of pelagic Sargassum influx events is linked to oceanic origin

Kristie S. T. Alleyne, Donald R. Johnson, FRANCIS C. NEAT, Hazel A. Oxenford et autres

The recent proliferation of pelagic Sargassum spp. in the Tropical Atlantic causes major ecological and socioeconomic impacts to the wider Caribbean when it washes ashore, with regional fisheries and tourism industries particularly affected. The Caribbean influxes have been tracked to a new …

se, us, bb (code pays fourni par la source)

Supplemental resources for "Designing Arduino Instruction for Novice Agriculture Students: Effects on Interest, Self-Efficacy, and Knowledge"

Donald R. Johnson

Lesson, activity, and instruments used in the study of novice Arduino users in a college of agriculture.

Supplemental resources for "Designing Arduino Instruction for Novice Agriculture Students: Effects on Interest, Self-Efficacy, and Knowledge"

Donald R. Johnson

Lesson, activity, and instruments used in the study of novice Arduino users in a college of agriculture.

Forecasting seasonal sargassum events across the tropical Atlantic: Overview and challenges

Robert Marsh, Hazel A. Oxenford, Shelly-Ann L. Cox, Donald R. Johnson et autres

Proliferation of sargassum across the tropical Atlantic since 2011 has motivated a range of forecasting methods. Statistical methods based on basin-scale satellite data are used to address seasonal timescales. Other methods involve explicit Lagrangian calculations of trajectories for particles that are representative …

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Controlled compositional gradients of electroformed gold and silver

Michael McBride, Jamie A. Stull, Enkeleda Dervishi, Donald R. Johnson et autres

Motivated by an interest in high-pressure research, thick (>1 mm) compositionally graded gold/silver (Au/Ag) films were electroformed. Systematic studies were performed to understand the role of processing temperature on the nucleation and growth kinetics and associated microstructure. Furthermore, as the electrolyte composition …

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Developments in Gd2O2S based pixelated-metallic aperture arrays

Brenden Wiggins, Cameron G. Wiggins, Donald R. Johnson, Oliver Humbach et autres

Radiographic imaging represents a vital capability within non-destructive assessment, quality control and fundamental science. This study focuses on Gd2O2S:Tb3+ based scintillating composites incorporated into pixelated-metallic aperture screens, attached to amorphous silicon-based flat panels. Performance metrics are explored through coupled MCNP6- FRED simulations; …

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