Adverse events have limited the use of bronchial thermoplasty (BT) in severe asthma. Hall et al sought to evaluate the effectiveness and safety of using 129Xe magnetic resonance imaging (129Xe MRI) ...to prioritize the most involved airways for guided BT. Thirty subjects with severe asthma were imaged with volumetric computed tomography and 129Xe MRI to quantitate segmental ventilation defects. Subjects were randomized to treatment of the six most involved airways in the first session (guided group) or a standard three-session BT (unguided). The primary outcome was the change in Asthma Quality of Life Questionnaire score from baseline to 12 weeks after the first BT for the guided group compared with after three treatments for the unguided group. Results of this pilot study suggest that similar short-term improvements can be achieved with one BT treatment guided by 129Xe MRI when compared with standard three-treatment-session BT with fewer periprocedure adverse events.
Pluto is the only planet in our solar system that has not yet been visited by a spacecraft from Earth. Beyond the orbit of Pluto lies the Kuiper-Belt: home to many primordial objects from the ...earliest days of the formation of the solar system, preserved in a cosmic deep freeze. The Johns Hopkins University/Applied Physics Laboratory (JHU/APL) is planning the mission for the Principal Investigator, Dr. S. Alan Stern of Southwest Research Institute. The planned design of the New Horizons spacecraft, along with a discussion of the design drivers, is presented. The design lifetime of the spacecraft would be 15.25 years. Measures taken to ensure the reliable operation of the spacecraft over the life of the planned mission are discussed.
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Adverse events have limited the use of bronchial thermoplasty (BT) in severe asthma.
We sought to evaluate the effectiveness and safety of using
Xe magnetic resonance imaging (
Xe MRI) to prioritize ...the most involved airways for guided BT.
Thirty subjects with severe asthma were imaged with volumetric computed tomography and
Xe MRI to quantitate segmental ventilation defects. Subjects were randomized to treatment of the six most involved airways in the first session (guided group) or a standard three-session BT (unguided). The primary outcome was the change in Asthma Quality of Life Questionnaire score from baseline to 12 weeks after the first BT for the guided group compared with after three treatments for the unguided group.
There was no significant difference in quality of life after one guided compared with three unguided BTs (change in Asthma Quality of Life Questionnaire guided = 0.91 95% confidence interval, 0.28-1.53; unguided = 1.49 95% confidence interval, 0.84-2.14;
= 0.201). After one BT, the guided group had a greater reduction in the percentage of poorly and nonventilated lung from baseline when compared with unguided (-17.2%;
= 0.009). Thirty-three percent experienced asthma exacerbations after one guided BT compared with 73% after three unguided BTs (
= 0.028).
Results of this pilot study suggest that similar short-term improvements can be achieved with one BT treatment guided by
Xe MRI when compared with standard three-treatment-session BT with fewer periprocedure adverse events.
The spin-structure functions g1 and g2, and the spin-dependent partial cross-section σTT have been extracted from the polarized cross-sections differences, Δσ∥(ν,Q2) and Δσ⊥(ν,Q2) measured for the ...He3→(e→,e′)X reaction, in the E97-110 experiment at Jefferson Lab. Polarized electrons with energies from 1.147 to 4.404 GeV were scattered at angles of 6∘ and 9∘ from a longitudinally or transversely polarized 3He target. The data cover the kinematic regions of the quasi-elastic, resonance production and beyond. From the extracted spin-structure functions, the first moments Γ1‾(Q2), Γ2(Q2) and ITT(Q2) are evaluated with high precision for the neutron in the Q2 range from 0.035 to 0.24GeV2. The comparison of the data and the chiral effective field theory predictions reveals the importance of proper treatment of the Δ degree of freedom for spin observables.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
On July 14, 2015, the New Horizons mission accomplished the first flyby of Pluto–Charon, achieving full mission success during its primary mission. Less than 4 years later, during its first extended ...mission, New Horizons flew by Arrokoth, a 36-km contact binary trans-Neptunian object in the Kuiper Belt, on January 1, 2019. Along the way, New Horizons imaged numerous distant Kuiper Belt objects, performed important heliophysics science including complex Lyman-α radiation scans, and measured the dust and zodiacal light from regions never before explored. This article provides an overview of the New Horizons spacecraft and its engineering performance, as well as potential strategies for extending the mission far beyond its original design lifetime. Details on the mass and power budgets, as well as descriptions of key innovations to meet the challenges posed by the mission, offer insight into the engineering accomplishments that led to mission success. Trended data on the power, thermal, and propulsion systems substantiate projections of the mission's potential to continue its exploration beyond the heliopause until ~2050.
The New Horizons Spacecraft Fountain, Glen H.; Kusnierkiewicz, David Y.; Hersman, Christopher B. ...
Space science reviews,
10/2008, Volume:
140, Issue:
1-4
Journal Article
Peer reviewed
Open access
The New Horizons spacecraft was launched on 19 January 2006. The spacecraft was designed to provide a platform for seven instruments designated by the science team to collect and return data from ...Pluto in 2015. The design meets the requirements established by the National Aeronautics and Space Administration (NASA) Announcement of Opportunity AO-OSS-01. The design drew on heritage from previous missions developed at The Johns Hopkins University Applied Physics Laboratory (APL) and other missions such as Ulysses. The trajectory design imposed constraints on mass and structural strength to meet the high launch acceleration consistent with meeting the AO requirement of returning data prior to the year 2020. The spacecraft subsystems were designed to meet tight resource allocations (mass and power) yet provide the necessary control and data handling finesse to support data collection and return when the one-way light time during the Pluto fly-by is 4.5 hours. Missions to the outer regions of the solar system (where the solar irradiance is 1/1000 of the level near the Earth) require a radioisotope thermoelectric generator (RTG) to supply electrical power. One RTG was available for use by New Horizons. To accommodate this constraint, the spacecraft electronics were designed to operate on approximately 200 W. The travel time to Pluto put additional demands on system reliability. Only after a flight time of approximately 10 years would the desired data be collected and returned to Earth. This represents the longest flight duration prior to the return of primary science data for any mission by NASA. The spacecraft system architecture provides sufficient redundancy to meet this requirement with a probability of mission success of greater than 0.85. The spacecraft is now on its way to Pluto, with an arrival date of 14 July 2015. Initial in-flight tests have verified that the spacecraft will meet the design requirements.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The siderophores of Bacillus anthracis are critical for the pathogen's proliferation and may be necessary for its virulence. Bacillus anthracis str. Sterne cells were cultured in iron free media and ...the siderophores produced were isolated and purified using a combination of XAD-2 resin, reverse-phase FPLC, and size exclusion chromatography. A combination of 1H and 13C NMR spectroscopy, UV spectroscopy and ESI-MS/MS fragmentation were used to identify the primary siderophore as petrobactin, a catecholate species containing unusual 3,4-dihydroxybenzoate moieties, previously only identified in extracts of Marinobacter hydrocarbonoclasticus. A secondary siderophore was observed and structural analysis of this species is consistent with that reported for bacillibactin, a siderophore observed in many species of bacilli. This is the first structural characterization of a siderophore from B. anthracis, as well as the first characterization of a 3,4-DHB containing catecholate in a pathogen.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The ratios of inclusive electron scattering cross sections of 4He, 12C, and 56Fe to 3He have been measured at 1 < xB <. At Q2 > 1.4 GeV2, the ratios exhibit two separate plateaus, at 1.5 < xB < 2 and ...at xB > 2.25. This pattern is predicted by models that include 2- and 3-nucleon short-range correlations (SRC). Relative to A = 3, the per-nucleon probabilities of 3-nucleon SRC are 2.3, 3.1, and 4.4 times larger for A = 4, 12, and 56. This is the first measurement of 3-nucleon SRC probabilities in nuclei.
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In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to an exotic baryon with strangeness S=+1 is seen in the K(+)n invariant mass spectrum. The peak ...is at 1.542+/-0.005 GeV/c(2) with a measured width of 0.021 GeV/c(2) FWHM, which is largely determined by experimental mass resolution. The statistical significance of the peak is (5.2+/-0.6)sigma. The mass and width of the observed peak are consistent with recent reports of a narrow S=+1 baryon by other experimental groups.
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