Morehead State University

The authors have no conflicts of interest related to this publication.

We present a concept for a robust 12U version of an orbiting cubesat explorer for lunar water as a follow on to the Lunar Ice Cube mission with an upgraded IR spectrometer, CLEW, described in earlier work (ref). CLEW has significantly enhanced spectral range and spatial resolution with a modest (25%) increase volume, mass, and power, despite a requirement for cooling to 70K that can be accomplished with the high heritage Ricor 508 cooler. Made possible by the larger volume, two, rather than one, star tracker, and three larger momentum wheels will greatly improve knowledge and control of pointing, and that, combined with the detector readout design, will create the capability for resolving features of 1 km or smaller at 100 km altitude within the 10 x 10 field of view. The detector readout design also allows us to operate within the 256 kbps bandwidth limitation if it remains in the future. The power system, including 100 W generating solar panels and double the backup battery capacity, will be more than adequate for the payload needs. One option for the propulsion system we will need for the larger spacecraft is to replace the 3U volume ion propulsion drive system used on Lunar Ice Cube with a higher specific impulse chemical propulsion system, such as the hydrazine system used by Capstone, the successful 12U lunar orbiter communication, navigation and tracking pathfinder. That would significantly reduce the duration of cruise and ability for station-keeping to stay in a desirable science orbit for a much longer period of time.

Abstract Grouping topographic indices (TIs) values, a topographic metric incorporating upslope contributing area and slope gradient, into topographic index classes (TIC) to estimate soil moisture variability has been shown to improve hydrologic model characterization of complex landscapes. However, the performance of TIC may be enhanced by understanding the inputs in its derivation. In this study, in situ soil moisture measurements across 25 locations in a 4.2 ha field and the k‐means clustering machine learning algorithm were used to identify the optimum number of classes for characterizing field soil moisture. The effect of using equal‐interval, equal‐area, k‐means, and Fisher classification approaches; U.S. Geological Survey (USGS) (1 and 9 m); and drone‐captured light detecting and ranging (LiDAR) digital elevation models (DEMs) re‐gridded to 0.25, 0.5, 1, 2, 3, 4, 5, and 10 m resolution was evaluated. The k‐means clustering, along with elbow analysis and Gap* statistics, identified the spatial pattern of the soil moisture in the field into three groups. Spearman's correlation between a three‐class TIC and the identified soil moisture patterns showed wide variability due to DEM resolution for TIC from drone‐captured LiDAR DEMs—from r = −0.41 to −0.17 for high resolution (0.25–4 m) to r = 0.52 to 0.58 for low resolution (10 m), compared to TIC derived from 1 and ∼9 m resolution USGS DEMs (r = 0.53–0.64). TIC generated using the equal‐interval approach best correlated with identified soil moisture patterns. Selecting the right classification approach, DEM type, and resolution are important considerations when using TI to estimate soil moisture patterns.

IntroductionPoultry litter (PL) compost and heat-treated PL-pellets (PP) are common organic fertilizer/soil amendments in specialty crop production and soil health management. However, such products may enhance survival and persistence of foodborne pathogens and their transfer to fresh produce.MethodsA replicated (n = 4) 2-year, randomized complete block field-plot inoculated-challenge study, with PL treatments (composted APL and PP) and cover crop/soil placement, was conducted to assess soil persistence/transfer of generic gE.colirif-R to cantaloupe, cucumber, spinach, and table radish, in cover-cropped USDA-National Organic Program (NOP) 8-years managed as certified plots. Amended soils were analyzed monthly for E. coli up through 90-120-day NOP required wait periods between PL application and produce harvest. Cantaloupe, cucumber, spinach, and table radish, grown compliant with NOP standards, were assayed at harvest for pathogens (Salmonella, Listeria monocytogenes, Staphylococcus aureus) and gE. coli.Results and discussionAll amended, inoculated soils were positive for the inoculated E. coli (6-log MPN/g) immediately after inoculation. At 90 dpi, all plot soils were positive for the inoculated gEcrif-R; by 120 dpi, gEcrif-R concentrations in soils declined significantly (p < 0.05) both in 2018 and 2019. No other pathogens (Salmonella, Listeria monocytogenes, Staphylococcus aureus) were detected at 0 or 90 dpi in plot soils. Generic Ecrif-R was detected on four of 16 cantaloupes, four of 16 cucumbers from APL plots; four of 20 radish bulbs from till incorporated and four from subsurface-applied APL tested positive for gEcrif-R at 90 dpi. By 120 dpi, only two spinach plants (n = 20) were positive from subsurface APL plots; no other pathogens or gEcrif-R were recovered for any crops in 2018–2019. Significant, consistent declines and decreasing survival throughout the growing seasons in populations of inoculated E. coli in soil, resulted in very low detection on any unwashed produce by 90 and 100 dpi in accord with NOP manure amendment-to-harvest wait times. Exposure to a combination of environmental conditions, including soil moisture, splash transfer of soil to produce, and temperatures (soil and air), impact E. coli populations in tilled and subsurface PL product-amended soils and on produce managed in compliance with organic production requirements.

Background: Platelets use SNARE-mediated exocytosis to maintain vascular integrity via the release from three types of granules: dense, α, and lysosomal. To understand how the SNAREs are regulated, we probed the role of Cysteine String Protein-α (CSPα), a potential t/Q-SNARE chaperone and assessed its effects on thrombosis and hemostasis. This abundant protein is the only detectible isoform from its respective family in platelets. Objective: To address the role of CSPα in platelets. Methods: We examined the platelet function and hemostatic phenotype of global CSPα -/- mice using several in vitro and in vivo assays, including an IDEXX hematology analyzer to measure platelet count and size. Platelet activation and morphology were examined using cytometry and transmission electron microscopy. ATP secretion was measured using a sensitive luminescent plate assay. Hemostasis was assessed using tail bleeding and ex vivo a BioFlux microfluidics system. The levels of platelet SNARE machinery and cargo were quantified by western blotting. Protein localization was examined by 3-Dimensional Structured Illumination Microscopy (3D-SIM) and subcellular fractionation. Results: Hematology data indicates that CSPα -/- mice have normal platelet size and counts, but leukocytes counts were significantly lower in CSPα -/- mice. CSPα -/- platelets have defective α- and dense granule release with minimum effects on lysosomal granule release. CSPα -/- platelets have reduced integrin activation in response to GPVI-specific agonists. Tail bleeding in CSPα -/- and CSPα +/- mice was significantly increased compared to wild-type littermates. Thrombus formation was also defective in CSPα -/- mice at low-shear rates in microfluidics assays. Loss of CSPα did not affect any of the proteins in the platelet secretory machinery, but it did interestingly cause a reduction in GPVI levels. Immunofluorescence experiments showed that CSPα colocalizes with markers for both α- and lysosomal granules. Subcellular fractionation studies showed that CSPα is present on membranes and not in lipid rafts. These results identify that CSPα is an essential element of the platelet secretory machinery and plays a significant role in thrombosis and hemostasis. Conclusions: These experiments indicate that CSPα has a role in platelet secretion and thus in thrombosis and hemostasis. These data fill gaps in our knowledge of CSPα’s physiological role and our understanding of how platelet exocytosis is controlled.