Application of Remote Sensing Techniques to Monitoring Soil Moisture

During the 1970 growing season, research was conducted to investigate the relationship between remote sensing imagery and soil moisture. Extensive aerial and ground truth data were collected and studied in order to evaluate the moisture supply and water use. The three hectare study site, located on the South Dakota State University James Valley Research and Extension Center, contained irrigated and non-irrigated sorghum and two fallow treatments. Results indicate that remote sensing is a feasible method for monitoring available soil moisture. Thirteen aerial missions were conducted between June 17 and October 5 at altitudes between 305 meters (1,000 feet) above ground level and 1525 meters (5,000 feet) above ground level. Photography was collected each flight with color reversal infrared film and three black and white films filtered for the green, red, and near infrared bands of the spectrum. A thermal infrared scanner and a precision radiation thermometer recorded earth-emitted radiation and temperature anomalies. Solameters measured both incoming and outgoing radiation. Imagery analyses were performed by three methods: 1. visual interpretation, 2. Use of a closed circuit television color encoding system specifically designed for imagery interpretation and overall film density analysis, and 3. Film density measurements. Film densities were corrected to account for seasonal changes in incoming radiation, amount of plant canopy, and reflectances of the crop and soil. Final analysis was accomplished by correlation of the soil moisture data with the film densities and corrected film densities. The results revealed that the soil-plant system viewed by the sensors provided information on the different soil moisture, the crop related the available moisture conditions of the soil profile. Of the three reflected the available moisture conditions of the soil profile. Of the three reflected radiation bands, the red band provided the best results for determination of soil moisture; the green band gave reasonable results throughout most of the season; and near infrared photography did not provide helpful indications of available soil moisture

Best Management Practices for Corn Production in South Dakota: Irrigation and Salt Management

In South Dakota, average annual precipitation ranges from less than 13 inches to nearly 30 inches, generally increasing from west to east (fig. 6.1). However, all regions of South Dakota can experience drought. Irrigation can reduce a crop’s dependence on natural rainfall and improve yields. To best capitalize on investment in irrigation equipment, it has been suggested that one should increase plant populations on irrigated land by 2,000 to 3,000 plants per acre (Aldrich et al. 1975). This chapter discusses how much irrigation water to apply and how to manage the salts contained in the water. If you are planning a new system or expanding an existing system, equipment and management options should be discussed with your local irrigation equipment dealer or Extension educator. A permit may be required to irrigate in South Dakota. For permit requirements, contact the South Dakota Department of Environment and Natural Resources (DENR)

Antimicrobial resistance (AMR) nanomachines: mechanisms for fluoroquinolone and glycopeptide recognition, efflux and/or deactivation

In this review, we discuss mechanisms of resistance identified in bacterial agents Staphylococcus aureus and the enterococci towards two priority classes of antibiotics—the fluoroquinolones and the glycopeptides. Members of both classes interact with a number of components in the cells of these bacteria, so the cellular targets are also considered. Fluoroquinolone resistance mechanisms include efflux pumps (MepA, NorA, NorB, NorC, MdeA, LmrS or SdrM in S. aureus and EfmA or EfrAB in the enterococci) for removal of fluoroquinolone from the intracellular environment of bacterial cells and/or protection of the gyrase and topoisomerase IV target sites in Enterococcus faecalis by Qnr-like proteins. Expression of efflux systems is regulated by GntR-like (S. aureus NorG), MarR-like (MgrA, MepR) regulators or a two-component signal transduction system (TCS) (S. aureus ArlSR). Resistance to the glycopeptide antibiotic teicoplanin occurs via efflux regulated by the TcaR regulator in S. aureus. Resistance to vancomycin occurs through modification of the D-Ala-D-Ala target in the cell wall peptidoglycan and removal of high affinity precursors, or by target protection via cell wall thickening. Of the six Van resistance types (VanA-E, VanG), the VanA resistance type is considered in this review, including its regulation by the VanSR TCS. We describe the recent application of biophysical approaches such as the hydrodynamic technique of analytical ultracentrifugation and circular dichroism spectroscopy to identify the possible molecular effector of the VanS receptor that activates expression of the Van resistance genes; both approaches demonstrated that vancomycin interacts with VanS, suggesting that vancomycin itself (or vancomycin with an accessory factor) may be an effector of vancomycin resistance. With 16 and 19 proteins or protein complexes involved in fluoroquinolone and glycopeptide resistances, respectively, and the complexities of bacterial sensing mechanisms that trigger and regulate a wide variety of possible resistance mechanisms, we propose that these antimicrobial resistance mechanisms might be considered complex ‘nanomachines’ that drive survival of bacterial cells in antibiotic environments

Measurement of the tt̄W and tt̄Z production cross sections in pp collisions at √s = 8 TeV with the ATLAS detector

The production cross sections of top-quark pairs in association with massive vector bosons have been measured using data from pp collisions at s√ = 8 TeV. The dataset corresponds to an integrated luminosity of 20.3 fb−¹ collected by the ATLAS detector in 2012 at the LHC. Final states with two, three or four leptons are considered. A fit to the data considering the tt̄W and tt̄Z processes simultaneously yields a significance of 5.0σ (4.2σ) over the background-only hypothesis for tt¯Wtt¯W (tt̄Z) production. The measured cross sections are σtt̄W = 369 + 100−91 fb and σtt̄Z = 176 + 58−52 fb. The background-only hypothesis with neither tt̄W nor tt̄Z production is excluded at 7.1σ. All measurements are consistent with next-to-leading-order calculations for the tt̄W and tt̄Z processes

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements