Search for single top-quark production via flavour-changing neutral currents at 8TeV with the ATLAS detector
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The result of a search for pair production of the supersymmetric partner of the Standard Model bottom quark ($\tilde{b}$ 1 ) is reported. The search uses 3.2 fb - 1 of pp collisions at $\sqrt{s}=13$ TeV collected by the ATLAS experiment at the Large Hadron Collider in 2015. Bottom squarks are searched for in events containing large missing transverse momentum and exactly two jets identified as originating from b-quarks. No excess above the expected Standard Model background yield is observed. Exclusion limits at 95 % confidence level on the mass of the bottom squark are derived in phenomenological supersymmetric R-parity-conserving models in which the $\tilde{b}$ 1 is the lightest squark and is assumed to decay exclusively via $\tilde{b}$ 1 →b$\tilde{χ}$$0\atop{1}$, where $\tilde{χ}$$0\atop{1}$ is the lightest neutralino. The limits significantly extend previous results; bottom squark masses up to 800 (840) GeV are excluded for the $\tilde{χ}$$0\atop{1}$ mass below 360 (100) GeV whilst differences in mass above 100 GeV between the $\tilde{b}$ 1 and the $\tilde{χ}$$0\atop{1}$ are excluded up to a $\tilde{b}$ 1 mass of 500 GeV.
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Measurements of fiducial integrated and differential cross sections for inclusive W + , W - and Z boson production are reported. They are based on 25.0±0.5pb -1 of pp collision data at √s=5.02 TeV collected with the ATLAS detector at the CERN Large Hadron Collider. Electron and muon decay channels are analysed, and the combined W + , W - and Z integrated cross sections are found to be σ W+ =2266±9 (stat)±29 (syst)±43 (lumi) pb, σ W- =1401±7 (stat)±18 (syst)±27 (lumi) pb, and σ Z =374.5±3.4 (stat)±3.6 (syst)±7.0 (lumi) pb, in good agreement with next-to-next-to-leading-order QCD cross-section calculations. These measurements serve as references for Pb+Pb interactions at the LHC at √sNN=5.02 TeV.
Inclusive and differential cross-sections for the production of a top-quark pair in association with a photon are measured with proton-proton collision data corresponding to an integrated luminosity of 36.1 fb –1 , collected by the ATLAS detector at the LHC in 2015 and 2016 at a centre-of-mass energy of 13 TeV. The measurements are performed in single-lepton and dilepton final states in a fiducial volume. Events with exactly one photon, one or two leptons, a channel-dependent minimum number of jets, and at least one b-jet are selected. Neural network algorithms are used to separate the signal from the backgrounds. The fiducial cross-sections are measured to be 521 ± 9(stat.) ± 41(sys.) fb and 69 ± 3(stat.) ± 4(sys.) fb for the single-lepton and dilepton channels, respectively. The differential cross-sections are measured as a function of photon transverse momentum, photon absolute pseudorapidity, and angular distance between the photon and its closest lepton in both channels, as well as azimuthal opening angle and absolute pseudorapidity difference between the two leptons in the dilepton channel. All measurements are in agreement with the theoretical predictions.
The inclusive cross-section for jet production in association with a Z boson decaying into an electron–positron pair is measured as a function of the transverse momentum and the absolute rapidity of jets using 19.9 fb -1 of $\sqrt{s}$ = 8 TeV proton–proton collision data collected with the ATLAS detector at the Large Hadron Collider. The measured Z + jets cross-section is unfolded to the particle level. The cross-section is compared with state-of-the-art Standard Model calculations, including the next-to-leading-order and next-to-next-to-leading-order perturbative QCD calculations, corrected for non-perturbative and QED radiation effects. The results of the measurements cover final-state jets with transverse momenta up to 1 TeV, and show good agreement with fixed-order calculations.
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Background: The chemoautotrophic bacterium Ralstonia eutropha can utilize H 2 /CO 2 for growth under aerobic conditions. While this microbial host has great potential to be engineered to produce desired compounds (beyond polyhydroxybutyrate) directly from CO 2 , little work has been done to develop genetic part libraries to enable such endeavors. Results: We report the development of a toolbox for the metabolic engineering of Ralstonia eutropha H16. We have constructed a set of broad-host-range plasmids bearing a variety of origins of replication, promoters, 5' mRNA stem-loop structures, and ribosomal binding sites. Specifically, we analyzed the origins of replication pCM62 (IncP), pBBR1, pKT (IncQ), and their variants. We tested the promoters P BAD , T7, P xyls/PM , P lacUV5 , and variants thereof for inducible expression. We also evaluated a T7 mRNA stem-loop structure sequence and compared a set of ribosomal binding site (RBS) sequences derived from Escherichia coli, R. eutropha, and a computational RBS design tool. Finally, we employed the toolbox to optimize hydrocarbon production in R. eutropha and demonstrated a 6-fold titer improvement using the appropriate combination of parts. Conclusion: We constructed and evaluated a versatile synthetic biology toolbox for Ralstonia eutropha metabolic engineering that could apply to other microbial hosts as well.
The pseudo-glycosyltransferase VldE catalyzes non-glycosidic C-N coupling between an unsaturated cyclitol and a saturated aminocyclitol with the conservation of the stereochemical configuration of the substrates to form validoxylamine A 7'-phosphate, the biosynthetic precursor of the antibiotic validamycin A. To study the molecular basis of its mechanism, the three-dimensional structures of VldE from Streptomyces hygroscopicus subsp. limoneus was determined in apo form, in complex with GDP, in complex with GDP and validoxylamine A 7'-phosphate, and in complex with GDP and trehalose. The structure of VldE with the catalytic site in both an “open” and “closed” conformation is also described. With these structures, the preferred binding of the guanine moiety by VldE, rather than the uracil moiety as seen in OtsA could be explained. The elucidation of the VldE structure in complex with the entirety of its products provides insight into the internal return mechanism by which catalysis occurs with a net retention of the stereochemical configuration of the donated cyclitol.
LCLS-II 1.3 GHz cryomodule production is well underway at Fermilab. Several dozen cavity/tuner systems have been tested, including tuning to 1.3 GHz, cold landing frequency, range/sensitivity of the slow tuner, and range/sensitivity of the fast tuner. All this testing information as well as lessons learned from tuner installation will be presented.
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This report describes methods and measurements of high-explosive products.
This report describes in detail a set of aspirational design and process targets to better understand the realistic economic potential for the production of algal biomass for subsequent conversion to biofuels and/or coproducts, based on the use of open pond cultivation systems and a series of dewatering operations to concentrate the biomass up to 20 wt% solids (ash-free dry weight basis).
Growing switchgrass (Panicum virgatum L.) as an intercrop in managed loblolly pine (Pinus taeda L.) plantations has emerged as a potential source of bioenergy feedstock. Utilizing land resources between pine trees to produce an energy crop can potentially reduce the demand for land resources used to produce food; however, converting conventionally managed forest land to this new intercropping system constitutes changes in land use and associated management practices, which may affect the environmental and economic sustainability of the land. The overall objective of this project is to evaluate the environmental effects of large-scale forest bioenergy crop production and utilize these results to optimize cropping systems in a manner that protects the important ecosystem services provided by forests while contributing to the development of a sustainable and economically-viable biomass industry in the southeastern United States.
This curriculum is intended to: teach you about Production Qualification & the Engineering Evaluation (EE) Plan, explain the course subject in detail, and provide references and guides that will help beyond this training.
The SECARB Anthropogenic Test at the Citronelle oil field in Mobile County, Alabama is the largest fully integrated coal-fired carbon capture, transportation and storage project in the United States. Constructed and funded by Southern Company and Mitsubishi Heavy Industries, the CO 2 capture facility at Alabama Power’s 2,657-megawatt Plant Barry captures up to 500 metric tons of CO 2 per day, the equivalent emissions from 25 MW of the plant’s power generation. Captured CO 2 is transported to the mature Citronelle oil field atop a 16,380 acre (66.3 km2 of surface area), geologic salt dome. Citronelle oil field is operated by Denbury Onshore, LLC. The CO 2 is injected through ten perforated intervals in the injection well casing at depths ranging from 9,436 ft to 9,800 ft into the porous and permeable sandstones of the Paluxy Formation. This report describes the transportation design and product specifications for captured CO 2 transported from the capture facility to the underground storage reservoir. CO 2 is transported through approximately 12 miles of pipeline from Plant Barry’s capture facility and is injected into the saline aquifer sandstones of the Paluxy formation at Citronelle oil field. The following outlines the details and characteristics of each point of transportation and the quality of CO 2 being transported.