Pure phase-encoded MRI and classification of solids

Here, the authors combine a pure phase-encoded magnetic resonance imaging (MRI) method with a new tissue-classification technique to make geometric models of a human tooth. They demonstrate the feasibility of three-dimensional imaging of solids using a conventional 11.7-T NMR spectrometer. In solid-state imaging, confounding line-broadening effects are typically eliminated using coherent averaging methods. Instead, the authors circumvent them by detecting the proton signal at a fixed phase-encode time following the radio-frequency excitation. By a judicious choice of the phase-encode time in the MRI protocol, the authors differentiate enamel and dentine sufficiently to successfully apply a new classification algorithm. This tissue-classification algorithm identifies the distribution of different material types, such as enamel and dentine, in volumetric data. In this algorithm, the authors treat a voxel as a volume, not as a single point, and assume that each voxel may contain more than one material. They use the distribution of MR image intensities within each voxel-sized volume to estimate the relative proportion of each material using a probabilistic approach. This combined approach, involving MRI and data classification, is directly applicable to bone imaging and hard-tissue contrast-based modeling of biological solids

Marquette Island: A Distinct Mafic Lithology Discovered by Opportunity

While rolling over the Meridiani Planum sedimentary terrane, the rover Opportunity has occasionally discovered large, > 10 cm erratics. Most of these have proven to be meteorites [1], but one - Bounce Rock - is a martian basaltic rock similar in composition to the meteorite EETA79001 lithology B [2]. Presently, Opportunity is intensively investigating an --30 cm tall rock named Marquette Island that may be a distinct type of martian mafic lithology. We report the results of its continuing investigation using the Microscopic Imager (MI); Mossbauer Spectrometer (MB) and Alpha Particle X-ray Spectrometer (APXS). A companion abstract discusses the results of Panoramic Camera (Pancam) imaging of the rock [3]

Improvements in quality of life in children following epicutaneous immunotherapy (EPIT) for peanut allergy in the PEPITES and PEOPLE studies

Background: Food allergy quality of life (FAQL) is impaired in children with peanut allergy. Food Allergy Quality of Life Questionnaires (FAQLQs) provide disease-specific insight into the burden of peanut allergy and potential FAQL changes after peanut immunotherapy. Objective: To examine FAQL changes in children after treatment with epicutaneous immunotherapy for peanut allergy (250 μg, daily epicutaneous peanut protein; DBV712 250 μg). Methods: FAQL was prospectively measured using the FAQLQ parent proxy form (Food Allergy Quality of Life Questionnaire-Parent Proxy Form [FAQLQ-PF], for children aged ≤12 years) and child form (Food Allergy Quality of Life Questionnaire-Child Form [FAQLQ-CF], child rated if aged ≥8 years) during the 12-month double-blind, randomized, controlled Peanut EPIT Efficacy and Safety Study (PEPITES) trial and the initial 12 months of the open-label PEPITES Open Label Extension Study (PEOPLE) follow-up study. Data were analyzed for between-group differences after treatment unblinding. Results: FAQLQs from placebo participants (FAQLQ-PF: 96; FAQLQ-CF: 47) and treatment group participants (FAQLQ-PF: 209; FAQLQ-CF: 105) were analyzed. Twenty-four–month global FAQL scores (FAQLQ-PF/FAQLQ-CF) were significantly improved in the treatment group versus the placebo group (least squares mean, 0.34, P = .008, and 0.46, P = .023, respectively). At 24 months, there was significant FAQLQ-PF score improvement in participants initially randomized to treatment who met the efficacy primary end point (n = 74; least squares mean, 0.55; P < .001) and in participants with any eliciting dose increase (n = 127; least squares mean, 0.66; P < .001). FAQLQ-PF improvements were observed in social dietary limitations (P = .002), food-related anxiety (P = .029), and emotional impact (P = .048) domains. FAQLQ-CF improvements were observed in risk of accidental exposure (P = .002) and allergen avoidance (P = .04) domains. Nearly all outcomes met a nontreatment context minimal clinically important difference previously cited for FAQLQ. Conclusions: Epicutaneous immunotherapy treatment was observed to be associated with significant global and domain-specific FAQL improvement (FAQLQ-PF/FAQLQ-CF), largely driven by increases in eliciting dose, in children with peanut allergy

Geochemical properties of rocks and soils in Gusev Crater, Mars: Results of the Alpha Particle X-Ray Spectrometer from Cumberland Ridge to Home Plate

Geochemical diversity of rocks and soils has been discovered by the Alpha Particle X-Ray Spectrometer (APXS) during Spirit&rsquo;s journey over Husband Hill and down into the Inner Basin from sol 470 to 1368. The APXS continues to operate nominally with no changes in calibration or spectral degradation over the course of the mission. Germanium has been added to the Spirit APXS data set with the confirmation that it occurs at elevated levels in many rocks and soils around Home Plate. Twelve new rock classes and two new soil classes have been identified at the Spirit landing site since sol 470 on the basis of the diversity in APXS geochemistry. The new rock classes are Irvine (alkaline basalt), Independence (low Fe outcrop), Descartes (outcrop similar to Independence with higher Fe and Mn), Algonquin (mafic-ultramafic igneous sequence), Barnhill (volcaniclastic sediments enriched in Zn, Cl, and Ge), Fuzzy Smith (high Si and Ti rock), Elizabeth Mahon (high Si, Ni, and Zn outcrop and rock), Halley (hematite-rich outcrop and rock), Montalva (high K, hematite-rich rock), Everett (high Mg, magnetite-rich rock), Good Question (high Si, low Mn rock), and Torquas (high K, Zn, and Ni magnetite-rich rock). New soil classes are Gertrude Weise (very high Si soil) and Eileen Dean (high Mg, magnetite-rich soil). Aqueous processes have played a major role in the formation and alteration of rocks and soils on Husband Hill and in the Inner Basin

Excluding Electroweak Baryogenesis in the MSSM

In the context of the MSSM the Light Stop Scenario (LSS) is the only region of parameter space that allows for successful Electroweak Baryogenesis (EWBG). This possibility is very phenomenologically attractive, since it allows for the direct production of light stops and could be tested at the LHC. The ATLAS and CMS experiments have recently supplied tantalizing hints for a Higgs boson with a mass of ~ 125 GeV. This Higgs mass severely restricts the parameter space of the LSS, and we discuss the specific predictions made for EWBG in the MSSM. Combining data from all the available ATLAS and CMS Higgs searches reveals a tension with the predictions of EWBG even at this early stage. This allows us to exclude EWBG in the MSSM at greater than (90) 95% confidence level in the (non-)decoupling limit, by examining correlations between different Higgs decay channels. We also examine the exclusion without the assumption of a ~ 125 GeV Higgs. The Higgs searches are still highly constraining, excluding the entire EWBG parameter space at greater than 90% CL except for a small window of m_h ~ 117 - 119 GeV.Comment: 24 Pages, 4 Figures (v3: fixed typos, minor corrections, added references

Biopsy depth after radiofrequency ablation of dysplastic Barrett's esophagus

After endoscopic radiofrequency ablation (RFA) of dysplastic Barrett's esophagus (BE), endoscopic biopsy samples are obtained to assess response to therapy. Whether these biopsies are of adequate depth to assess efficacy is unknown

Multiplicity Structure of the Hadronic Final State in Diffractive Deep-Inelastic Scattering at HERA

The multiplicity structure of the hadronic system X produced in deep-inelastic processes at HERA of the type ep -> eXY, where Y is a hadronic system with mass M_Y< 1.6 GeV and where the squared momentum transfer at the pY vertex, t, is limited to |t|<1 GeV^2, is studied as a function of the invariant mass M_X of the system X. Results are presented on multiplicity distributions and multiplicity moments, rapidity spectra and forward-backward correlations in the centre-of-mass system of X. The data are compared to results in e+e- annihilation, fixed-target lepton-nucleon collisions, hadro-produced diffractive final states and to non-diffractive hadron-hadron collisions. The comparison suggests a production mechanism of virtual photon dissociation which involves a mixture of partonic states and a significant gluon content. The data are well described by a model, based on a QCD-Regge analysis of the diffractive structure function, which assumes a large hard gluonic component of the colourless exchange at low Q^2. A model with soft colour interactions is also successful.Comment: 22 pages, 4 figures, submitted to Eur. Phys. J., error in first submission - omitted bibliograph

Multi-Jet Event Rates in Deep Inelastic Scattering and Determination of the Strong Coupling Constant

Jet event rates in deep inelastic ep scattering at HERA are investigated applying the modified JADE jet algorithm. The analysis uses data taken with the H1 detector in 1994 and 1995. The data are corrected for detector and hadronization effects and then compared with perturbative QCD predictions using next-to-leading order calculations. The strong coupling constant alpha_S(M_Z^2) is determined evaluating the jet event rates. Values of alpha_S(Q^2) are extracted in four different bins of the negative squared momentum transfer~\qq in the range from 40 GeV2 to 4000 GeV2. A combined fit of the renormalization group equation to these several alpha_S(Q^2) values results in alpha_S(M_Z^2) = 0.117+-0.003(stat)+0.009-0.013(syst)+0.006(jet algorithm).Comment: 17 pages, 4 figures, 3 tables, this version to appear in Eur. Phys. J.; it replaces first posted hep-ex/9807019 which had incorrect figure 4