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Full-Text Articles in Inorganic Chemicals

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer Jul 2016

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).


In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer Jul 2016

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).


In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer Jul 2016

In-Season N Fertilization Strategies Using Active Sensors, Daniel Barker, John Sawyer

John E. Sawyer

The objectives of this project were to measure corn yield response to applied nitrogen (N) fertilizer based on active canopy sensing during the mid-vegetative corn growth stage (V10) and compare yield and N use efficiency between pre-plant N (PP-N), pre-plant + sensor N (PP+S-N), split N strategy (SNS), and rescue N strategy (RNS).


Impacts Of Cover Crops On Phosphorus And Nitrogen Loss With Surface Runoff, Antonio Mallarino, Richard Cruse, Dan Jaynes, John Sawyer, Pablo Barbieri Jul 2016

Impacts Of Cover Crops On Phosphorus And Nitrogen Loss With Surface Runoff, Antonio Mallarino, Richard Cruse, Dan Jaynes, John Sawyer, Pablo Barbieri

John E. Sawyer

Iowa research has demonstrated that cover crops can improve soil productivity and water quality by increasing soil organic matter and reducing nitrate nitrogen (N) leaching. Other research has investigated and is investigating the agronomic and economic viability of using cereal rye cover crops in continuous corn or corn-soybean rotations. However, no Iowa research has evaluated under natural rainfall the impact of cover crops on phosphorus (P) and N loss with surface runoff interacting with other management practices. The need for this type of research was indicated in the Iowa Nutrient Reduction Strategy documents. This effort assessed what would be needed …


Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers Jul 2016

Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers

John E. Sawyer

Corn Belt corn and soybean producers are increasingly challenged to maximize crop production while addressing the contributions farm practices make to Gulf hypoxia. Based on the need for nitrate-N reductions to meet water quality goals, new management practices are needed to reduce nitrate-N losses at minimal cost and maximum economic benefits. This three-year field research and demonstration project is evaluating various promising N management methods and technologies by documenting the nitrate-N export and crop yield from various systems.


Cross-Sector Review Of Drivers And Available 3rs Approaches For Acute Systemic Toxicity Testing, Troy Seidle, Sally Robinson, Tom Holmes, Stuart Creton, Pilar Prieto, Julia Scheel, Magda Chlebus Dec 2014

Cross-Sector Review Of Drivers And Available 3rs Approaches For Acute Systemic Toxicity Testing, Troy Seidle, Sally Robinson, Tom Holmes, Stuart Creton, Pilar Prieto, Julia Scheel, Magda Chlebus

Troy Seidle, PhD

Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or …