Estimation of Optimal Biomass Removal Rate Based on Tolerable Soil Erosion for Single-Pass Crop Grain and Biomass Harvesting System

As the demand for biomass feedstocks grows, it is likely that agricultural residue will be removed in a way that compromises soil sustainability due to increased soil erosion, depletion of organic matter, and deterioration of soil physical characteristics. Since soil erosion from agricultural fields depends on several factors including soil type, field terrain, and cropping practices, the amount of biomass that can be removed while maintaining soil tilth varies substantially over space and time. The RUSLE2 soil erosion model, which takes into account these spatio-temporal variations, was used to estimate tolerable agricultural biomass removal rates at field scales for a single-pass crop grain and biomass harvesting system. Soil type, field topography, climate data, management practices, and conservation practices were stored in individual databases on a state or county basis. Geographic position of the field was used as a spatial key to access the databases to select site-specific information such as soil, topography, and management related parameters. These parameters along with actual grain yield were provided as inputs to the RUSLE2 model to calculate yearly soil loss per unit area of the field. An iterative technique was then used to determine site-specific tolerable biomass removal rates that keep the soil loss below the soil loss thresholds (T) of the field. The tolerable removal rates varied substantially with field terrain, crop management practices, and soil type. At a location in a field in Winnebago county, Iowa, with ~1% slope and conventional tillage practices, up to 98% of the 11 Mg ha-1 total above-ground biomass was available for collection with negligible soil loss. There was no biomass available to remove with conventional tillage practices on steep slopes, as in a field in Crawford county, Iowa, with a 12.6% slope. If no-till crop practices were adopted, up to 70% of the total above-ground biomass could be collected at the same location with 12.6% slope. In the case of a soybean-corn rotation with no-till practices, about 98% of total biomass was available for removal at the locations in the Winnebago field with low slopes, whereas 77% of total biomass was available at a location in the Crawford field with a 7.5% slope. Tolerable removal rates varied substantially over an agricultural field, which showed the importance of site-specific removal rate estimation. These removal rates can be useful in developing recommended rates for producers to use during a single-pass crop grain and biomass harvesting operation. However, this study only considered the soil erosion tolerance level in estimating biomass removal rates. Before providing the final recommendation to end users, further investigations will be necessary to study the potential effects of continuous biomass removal on organic matter content and other biophysical properties of the soil

Pseudoacromegaly

© 2018 Elsevier Inc. Individuals with acromegaloid physical appearance or tall stature may be referred to endocrinologists to exclude growth hormone (GH) excess. While some of these subjects could be healthy individuals with normal variants of growth or physical traits, others will have acromegaly or pituitary gigantism, which are, in general, straightforward diagnoses upon assessment of the GH/IGF-1 axis. However, some patients with physical features resembling acromegaly – usually affecting the face and extremities –, or gigantism – accelerated growth/tall stature – will have no abnormalities in the GH axis. This scenario is termed pseudoacromegaly, and its correct diagnosis can be challenging due to the rarity and variability of these conditions, as well as due to significant overlap in their characteristics. In this review we aim to provide a comprehensive overview of pseudoacromegaly conditions, highlighting their similarities and differences with acromegaly and pituitary gigantism, to aid physicians with the diagnosis of patients with pseudoacromegaly.PM is supported by a clinical fellowship by Barts and the London Charity. Our studies on pituitary adenomas and related conditions received support from the Medical Research Council, Rosetrees Trust and the Wellcome Trust

Dielectric Spectroscopic Aerosol Sensing in the Compressed Air Stream

Contamination of compressed air can reduce its utility and lead to costly failure of pneumatic components. Monitoring the presence of contaminants in the air could provide early warning to take measures that could retain pneumatic system usefulness. The sensing of contaminants in a compressed air stream using dielectric spectroscopy has good potential for a viable commercial sensor for pneumatic systems based on the differences in dielectric properties between air and common contaminants such as metal, silicon, and water condensate. Oil mist, while not a contaminant, is required for lubricating pneumatic components, so its presence is important. Two tests were performed using a dielectric sensor capable of spectroscopic measurement to investigate the efficacy of dielectric spectroscopy in detecting the presence of liquids (water and oil) in compressed air. The first test used deionized water, and the second test used a light lubricant oil (Sunoco Sunvis 932, Sunoco, PA). Industrial spray nozzles were used to atomize these liquids, which were then entrained in a compressed airstream and passed through the dielectric sensor. Visualization of spectroscopic measurements and their transformation using principal component analysis (PCA) showed that the sensor has potential to differentiate the presence and absence of liquid droplets in compressed airstream. This separation of two cases based on the spectroscopic data suggests that dielectric spectroscopy could be used to detect these two liquids in the compressed airstream.This paper is from 2016 ASABE Annual International Meeting, Paper No. 162461483, pages 1-8 (doi: 10.13031/aim.20162461483). St. Joseph, Mich.: ASABE. Posted with permission</p