The accuracy and unit cost of sensors are important factors for a continuous soil moisture monitoring system. This study compares the accuracy of four soil moisture sensors differing in unit costs in coarse-, fine-, and medium-textured soils. The sensor outputs were recorded for the VWC, ranging from 0% to 50%. Low-cost capacitive and resistive sensors were evaluated with and without the external 16-bit analog-to-digital converter ADS1115 to improve their performances without adding much cost. Without ADS1115, using only Arduino’s built-in analog-to-digital converter, the low-cost sensors had a maximum RMSE of 4.79% (v/v) for resistive sensors and 3.78% for capacitive sensors in medium-textured soil. The addition of ADS1115 showed improved performance of the low-cost sensors, with a maximum RMSE of 2.64% for resistive sensors and 1.87% for capacitive sensors. The higher-end sensors had an RMSE of up to 1.8% for VH400 and up to 0.95% for the 5TM sensor. The RMSE differences between higher-end and low-cost sensors with the use of ADS1115 were not statistically significant.
Camelina (Camelina sativa) can be used to make biodiesel or biojet fuel. This study compares life-cycle energy, environmental impact and economic performance of making biodiesel versus biojet fuel from camelina oil. The data for camelina field production was obtained from a grower in western Washington, USA. Camelina seeds were crushed, and biodiesel and biojet fuel were produced at the University of Idaho's advanced biofuel research lab. Biodiesel was made via a transesterification reaction, and biojet was made using a technology called hydroprocessed renewable jet fuel. This research found that for a base-case scenario, where transportation and fuel additives were not needed, the ratio of energy in produced biofuel to its life-cycle energy was 3.6 for biodiesel and 1.8 for biojet fuel. Biodiesel reduced life-cycle GHG emissions by 69% compared to conventional diesel. In contrast, camelina biojet reduced GHG emissions by 56.6% compared to jet-A fuel. The cost of ingredients and utilities to make biodiesel was US 75¢/L compared to $2.19/L for biojet fuel taking no credit for byproducts. Considering the potential demand for biodiesel, the price of diesel, and price of jet fuel, it was concluded that biojet fuel is unlikely to compete economically with biodiesel in the foreseeable future.
Spaceflight Associated Neuro-ocular Syndrome (SANS) is associated with acquired optic disc edema, hyperopia, and posterior globe flattening in some astronauts during long-duration spaceflight possibly due to the headward fluid redistribution in microgravity. The goal of this study was to assess whether strict head-down tilt (HDT) bed rest as a spaceflight analog would produce globe flattening and whether centrifugation could prevent these changes. Twenty-four healthy subjects separated into 3 groups underwent 60 days of strict 6° HDT bed rest: one control group with no countermeasure (n=8) and two countermeasure groups exposed to 30 min daily of short-arm centrifugation as a means of artificial gravity (AG), either intermittent (iAG, n=8) or continuous (cAG, n=8). Magnetic resonance images (MRI) were collected at baseline, HDT-day 14, HDT-day 52, and 3 days after bed rest. An automated method was applied to quantify posterior globe volume displacement compared to baseline scans. On average, subjects showed an increasing degree of globe volume displacement with bed rest duration (mean ± SE: 1.41 ± 1.01 mm3 on HDT14 and 4.04 ± 1.19 mm3 on HDT52) that persisted post-bed rest (5.51 ± 1.26 mm3)). Application of 30 min daily AG did not have a significant impact on globe volume displacement (p = 0.42 for cAG and p = 0.93 for iAG compared to control). These results indicate that strict 6° HDT bed rest produced displacement of the posterior globe with a trend of increasing displacement with longer duration which was not prevented by daily 30 min exposure to AG.
Dual upflow reactive filtration by a slowly moving sand bed with continuously renewed, hydrous ferric oxide‐coated sand is used for removing polluting substances and for meeting the ultralow 0.05 mg/l total phosphorus discharge permit limits at a 1.2 million liters per day (0.32 million gallons per day) water resource recovery facility in Plummer, Idaho, in the United States. A life cycle assessment (LCA) of this reactive filtration installation was carried out to assess the environmental hotspots in the system and analyze alternative system configurations with a focus on CO2 equivalent (CO2e) global warming potential, freshwater and marine eutrophication, and mineral resource scarcity. “What if” scenarios with alternative inputs for the energy, metal salts, and air compressor optimization show trade‐offs between the impact categories. Key results that show a comparative reduction of global warming potential include the use of Fe versus Al metal salts, the use of renewable energy, and the energy efficiency benefit of optimizing process inputs, such as compressor air pressure, to match operational demand. The LCA shows a 2 × 10−2 kg CO2e footprint per cubic meter of water, with 47% from housing concrete, and an overall freshwater eutrophication impact reduced by 99% versus no treatment. The use of renewable hydropower energy at this site isolates construction concrete as a target for lowering the CO2e footprint.Practitioner Points: The main LCA eco‐impact hotspots in this dual reactive filtration tertiary treatment are construction concrete and the ferric sulfate used. Iron salts show smaller impact in global warming, freshwater eutrophication, and mineral resource scarcity than “what if scenario” aluminum salts. The energy mix for this site is predominantly hydropower; other energy mix “what if” scenarios show larger impacts. Operational energy efficiency and thermodynamic analysis show that fine tuning the air compressor helps reduce carbon footprint and energy use. LCA shows a favorable 2 x 10‐2 kg CO2e/m3 water impact with 99% reduction of freshwater eutrophication potential versus no treatment.
There is a need for a small-scale, laboratory treadmill to investigate impacts of neonatal locomotion on neuromuscular and musculoskeletal development in small animal models. Adult mice and rats are routinely assessed using commercially available treadmills, but these treadmills can be relatively expensive and they may lack features needed to evaluate developing animals. Therefore, to overcome these limitations, a new treadmill was designed, built and calibrated. This open-source treadmill was designed specifically for neonatal and postnatal mice and rats, and it fits within a neonatal incubator. By using predominantly off-the-shelf and 3D printed components, and a microcontroller, this treadmill was low cost and easy to reproduce. The design also included variable incline, and a transparent belt and enclosures for video and gait analysis. A touchscreen interface provided user-friendly control over belt speed and run time. Moreover, validation experiments showed high accuracy in belt speed control, allowing for tightly regulated experimental conditions. Overall, this new low-cost, open-source, variable speed and incline treadmill can be used to advance understanding of neonatal locomotion, and neuromuscular and musculoskeletal development.