Determining potential sources of race non-specific resistance to the late blight pathogen, Phytophthora infestans (Mont.) de Bary, in advanced breeding materials of cultivated potato, Solanum tuberosum L.

Phytophthora infestans (Mont.) de Bary, the causal agent of late blight disease of potato, is widely considered to be the most important plant disease of potato. The presence of major genes (R-genes) in breeding materials under improvement for resistance to this oomycete plant pathogen has created difficulties in the identification of minor genes (polygenes), and has hindered breeding efforts focused on concentrating sources of race-nonspecific resistance into the cultivated potato (Solanum tuberosum L.). The International Potato Center (CIP) responded to this challenge in the 1990's by developing a methodology for R-gene extraction by use of detached leaf assay experimentation. The present study analyzes 31 advanced clones of the LBHT population, under improvement at CIP for race-nonspecific resistance to late blight disease and performance under elevated temperatures (>18 degrees Celcius), to determine potential sources of race-nonspecific resistance in the absence of known, Solanum demissum Lindl., derived R-genes. As a second objective we compared the disease response of the 31 advanced clones challenged with isolates; PE8006, Pox109, Pox155, and Pox110, in detached leaf assay experiments, with disease responses observed in previous field trials, where materials were challenged with the prevalent field inoculum found in Oxapampa, Peru, in order to validate methodology.The nine advanced clones; 398180.292, 398190.89, 398208.219, 398208.704, 302531.43, 302533.49, 302534.43, 302542.62, and 302551.26, are reported to be either free of Solanum demissum derived R-genes or containing partially incompatible R-genes. From within these nine clones, a single clone (302551.26) demonstrated a response to inoculation by both a race 0 (Isolate PE8006) as well as the three complex races tested, which exceeded 50% mean lesion area in detached leaf assays. This response was confirmed by field evaluations. These results indicate that clone 302551.26 has the greatest potential to be free of known S. demissum derived R-genes according to established methodology. Of the nine advanced clones of interest, three clones (398180.292, 398190.89, and 398208.704) have demonstrated levels of resistance lower than 50% across both lab and field evaluations. These materials may contain either, partially defeated R-genes or high levels of polygenic resistance to P. infestans. The horizontal character of their resistance could be used to the benefit of breeding programs working towards the objectives of improving race-nonspecific resistance to P. infestans.Using the Pearson correlation coefficient it was determined that a correlation at P less than or equal to 0.001 exists between the evaluation factors of detached leaf assay sporulation intensity (Lab PI) and detached leaf assay lesion area (Lab LA) within each individual isolate of P. infestans. However, a correlation between the factors of evaluation, (Lab LA) and field evaluation of lesion area (Field LA) were found in only a single complex isolate, Pox109 at P less than or equal to 0.05. These results validate the use of Lab PI and Lab LA together to increase certainty in resistance responses of materials tested, as well as, demonstrate that the use of known lab isolates in screening resistant materials is largely unrepresentative of virulence found in the seasonal field inoculum in Oxapampa, Peru

Biology and management of bacterial spot of tomato in Oklahoma

In surveys of tomato fields during 2018 and 2019, bacterial spot was the most frequent foliar disease (72% of fields) followed by Septoria leaf spot (7%), and early blight (7%). Isolates of Xanthomonas spp. from 1998-2014 and those from 2018-2019 were identified to species using sequences of a 420 bp region of the hrp gene cluster amplified by the RST65/RST69 primers. The 1998-2014 isolates were X. perforans (n=17), X. gardneri (n=1), and X. vesicatoria (n=1); while the 2018-2019 isolates were also mostly X. perforans (n=42) followed by X. euvesicatoria (n=7) and X. gardneri (n=2). Races of X. perforans isolates included race T3 (n=15) and race T4 (n=6). Applications of bacteriophage, Bacillus amyloliquefaciens, acibenzolar-s-methyl, and copper bactericides were evaluated in field trials in 2018 and 2019. All treatments except B. amyloliquefaciens reduced disease levels, but none were as effective as copper hydroxide alone and a copper-mancozeb tank-mix. Alternatives to copper programs generally provided variable control with bacteriophage being the most consistent. However, none of the bactericide treatments increased yield compared to the non-treated control. In the absence of highly effective bactericide treatments and resistant cultivars, other preventive strategies such as sanitation, volunteer management, and crop rotation are critical to limit pathogen carryover and prevent early disease development. Race structure is diverse within the state. Host plant resistance should combine multiple resistance genes to be of greatest benefit to producers in the region

Analyzing the Effect of Air Capacitor Turbocharging Single Cylinder Engines on Fuel Economy and Emissions Through Modeling and Experimentation

Turbocharging can provide a cost effective means for increasing the power output and fuel economy of an internal combustion engine. A turbocharger added to an internal combustion engine consists of a coupled turbine and compressor. Currently, turbocharging is common in multi-cylinder engines, but it is not commonly used on single-cylinder engines due to the phase mismatch between the exhaust stroke (when the turbocharger is powered) and the intake stroke (when the engine intakes the compressed air). The proposed method adds an air capacitor, an additional volume in series with the intake manifold, between the turbocharger compressor and the engine intake, to buffer the output from the turbocharger compressor and deliver pressurized air during the intake stroke. This research builds on previous work where it was shown experimentally that a power gain of 29% was achievable and that analytically a power gain of 40-60% was possible using a turbocharger and air capacitor system. The goal of this study is to further analyze the commercial viability of this technology by analyzing the effect of air capacitor turbocharging on emissions, fuel economy, and power density. An experiment was built and conducted that looked at how air capacitor sizing affected emissions, fuel economy, and the equivalence ratio. The experimental data was then used to calibrate a computational model built in Ricardo Wave. Finally this model was used to evaluate strategies to further improve the performance of a single cylinder diesel turbocharged engine with an air capacitor.Massachusetts Institute of Technology. Tata Center for Technology and DesignNational Science Foundation (U.S.). Graduate Research Fellowship (Grant No. 1122374

Seabasing and joint expeditionary logistics

Student Integrated ProjectIncludes supplementary material. Executive Summary and Presentation.Recent conflicts such as Operation Desert Shield/Storm and Operation Iraqi Freedom highlight the logistics difficulties the United States faces by relying on foreign access and infrastructure and large supply stockpiles ashore to support expeditionary operations. The Navy's transformational vision for the future, Sea Power 21, involves Seabasing as a way to address these difficulties by projecting and sustaining joint forces globally from the sea. This study analyzes logistics flow to, within and from a Sea Base to an objective, and the architectures and systems needed to rapidly deploy and sustain a brigade-size force. Utilizing the Joint Capabilities Integration and Development System (JCIDS), this study incorporates a systems engineering framework to examine current systems, programs of record and proposed systems out to the year 2025. Several capability gaps that hamper a brigade-size force from seizing the initiative anywhere in the world within a 10-day period point to a need for dedicated lift assets, such as high-speed surface ships or lighter-than-air ships, to facilitate the rapid formation of the Sea Base. Additionally, the study identifies the need for large-payload/high-speed or load-once/direct-to- objective connector capabilities to minimize the number of at-sea transfers required to employ such a force from the Sea Base in 10 hrs. With these gaps addressed, the Joint Expeditionary Brigade is supportable from the Sea Base.http://archive.org/details/seabasingndjoint109456918N

RELICS: Strong Lens Models for Five Galaxy Clusters From the Reionization Lensing Cluster Survey

Strong gravitational lensing by galaxy clusters magnifies background galaxies, enhancing our ability to discover statistically significant samples of galaxies at z>6, in order to constrain the high-redshift galaxy luminosity functions. Here, we present the first five lens models out of the Reionization Lensing Cluster Survey (RELICS) Hubble Treasury Program, based on new HST WFC3/IR and ACS imaging of the clusters RXC J0142.9+4438, Abell 2537, Abell 2163, RXC J2211.7-0349, and ACT-CLJ0102-49151. The derived lensing magnification is essential for estimating the intrinsic properties of high-redshift galaxy candidates, and properly accounting for the survey volume. We report on new spectroscopic redshifts of multiply imaged lensed galaxies behind these clusters, which are used as constraints, and detail our strategy to reduce systematic uncertainties due to lack of spectroscopic information. In addition, we quantify the uncertainty on the lensing magnification due to statistical and systematic errors related to the lens modeling process, and find that in all but one cluster, the magnification is constrained to better than 20% in at least 80% of the field of view, including statistical and systematic uncertainties. The five clusters presented in this paper span the range of masses and redshifts of the clusters in the RELICS program. We find that they exhibit similar strong lensing efficiencies to the clusters targeted by the Hubble Frontier Fields within the WFC3/IR field of view. Outputs of the lens models are made available to the community through the Mikulski Archive for Space TelescopesComment: Accepted to Ap

RELICS: High-Resolution Constraints on the Inner Mass Distribution of the z=0.83 Merging Cluster RXJ0152.7-1357 from strong lensing

Strong gravitational lensing (SL) is a powerful means to map the distribution of dark matter. In this work, we perform a SL analysis of the prominent X-ray cluster RXJ0152.7-1357 (z=0.83, also known as CL 0152.7-1357) in \textit{Hubble Space Telescope} images, taken in the framework of the Reionization Lensing Cluster Survey (RELICS). On top of a previously known $z=3.93$ galaxy multiply imaged by RXJ0152.7-1357, for which we identify an additional multiple image, guided by a light-traces-mass approach we identify seven new sets of multiply imaged background sources lensed by this cluster, spanning the redshift range [1.79-3.93]. A total of 25 multiple images are seen over a small area of ~0.4 $arcmin^2$, allowing us to put relatively high-resolution constraints on the inner matter distribution. Although modestly massive, the high degree of substructure together with its very elongated shape make RXJ0152.7-1357 a very efficient lens for its size. This cluster also comprises the third-largest sample of z~6-7 candidates in the RELICS survey. Finally, we present a comparison of our resulting mass distribution and magnification estimates with those from a Lenstool model. These models are made publicly available through the MAST archive.Comment: 15 Pages, 7 Figures, 4 Tables Accepted for publication in Ap

The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe

The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay --- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions. LBNE is conceived around three central components: (1) a new, high-intensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a near neutrino detector just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is approximately 1,300 km from the neutrino source at Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions. With its exceptional combination of experimental configuration, technical capabilities, and potential for transformative discoveries, LBNE promises to be a vital facility for the field of particle physics worldwide, providing physicists from around the globe with opportunities to collaborate in a twenty to thirty year program of exciting science. In this document we provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess.Comment: Major update of previous version. This is the reference document for LBNE science program and current status. Chapters 1, 3, and 9 provide a comprehensive overview of LBNE's scientific objectives, its place in the landscape of neutrino physics worldwide, the technologies it will incorporate and the capabilities it will possess. 288 pages, 116 figure