Disc polarization from both emission and scattering of magnetically aligned grains: the case of NGC 1333 IRAS 4A1

Stars and planetary system

Heavy quarkonium: progress, puzzles, and opportunities

A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations. The plethora of newly-found quarkonium-like states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b}, and b\bar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K. Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D. Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A. Petrov, P. Robbe, A. Vair

52 Genetic Loci Influencing Myocardial Mass.

BACKGROUND: Myocardial mass is a key determinant of cardiac muscle function and hypertrophy. Myocardial depolarization leading to cardiac muscle contraction is reflected by the amplitude and duration of the QRS complex on the electrocardiogram (ECG). Abnormal QRS amplitude or duration reflect changes in myocardial mass and conduction, and are associated with increased risk of heart failure and death. OBJECTIVES: This meta-analysis sought to gain insights into the genetic determinants of myocardial mass. METHODS: We carried out a genome-wide association meta-analysis of 4 QRS traits in up to 73,518 individuals of European ancestry, followed by extensive biological and functional assessment. RESULTS: We identified 52 genomic loci, of which 32 are novel, that are reliably associated with 1 or more QRS phenotypes at p < 1 × 10(-8). These loci are enriched in regions of open chromatin, histone modifications, and transcription factor binding, suggesting that they represent regions of the genome that are actively transcribed in the human heart. Pathway analyses provided evidence that these loci play a role in cardiac hypertrophy. We further highlighted 67 candidate genes at the identified loci that are preferentially expressed in cardiac tissue and associated with cardiac abnormalities in Drosophila melanogaster and Mus musculus. We validated the regulatory function of a novel variant in the SCN5A/SCN10A locus in vitro and in vivo. CONCLUSIONS: Taken together, our findings provide new insights into genes and biological pathways controlling myocardial mass and may help identify novel therapeutic targets

Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target

The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About 1011 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to (3.27±0.07) × 1011 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill

Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment

In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved

Self-assembly in aqueous solution of a modified amyloid beta peptide fragment

The self-assembly in films dried from aqueous solutions of a modified amyloid beta peptide fragment is studied. We focus on sequence A beta(16-20), KLVFF, extended by two alanines at the N-terminus to give AAKLVFF. Self-assembly into twisted ribbon fibrils is observed, as confirmed by transmission electron microscopy (TEM). Dynamic light scattering reveals the semi-flexible nature of the AAKLVFF fibrils, while polarized optical microscopy shows that the peptide fibrils crystallize after an aqueous solution of AAKLVFF is matured over 5 days. The secondary structure of the fibrils is studied by FT-IR, circular dichroism and X-ray diffraction (XRD), which provide evidence for beta-sheet structure in the fibril. From high resolution TEM it is concluded that the average width of an AAKLVFF fibril is (63 +/- 18) nm, indicating that these fibrils comprise beta-sheets with multiple repeats of the unit cell, determined by XRD to have b and c dimensions 1.9 and 4.4 nm with an a axis 0.96 nm, corresponding to twice the peptide backbone spacing in the antiparallel beta-sheet. (C) 2008 Elsevier B.V. All rights reserved

Further investigation of the validity and reliability of the photographic figure rating scale for body image assessment

Previous studies have not fully investigated the psychometric properties of the Photographic Figure Rating Scale (PFRS). In 2 studies, we report on the test–retest reliability and convergent validity of ratings derived from the PFRS. In Study 1, 322 female university students in Britain provided self-ratings on the PFRS and objectively measured body mass index (BMI); a subsample of 132 women also completed the task after 5 weeks. In Study 2, 243 women from the community in Austria completed the PFRS along with a battery of other body image scales. Results of Study 1 showed that ratings on the PFRS had good test–retest reliability (all rs > .87) and good convergent validity in relation to BMI. Results of Study 2 showed that PFRS-derived body dissatisfaction scores were significantly correlated with a range of body image variables. These results provide evidence for the convergent validity and good test–retest reliability of the PFRS

Experimental studies of ignition behaviour and combustion reactivity of pulverized fuel particles

A pulse ignition technique, whereby a small mass of fine coal or char particles is fed into a drop-tube furnace, was used to evaluate the ignition characteristics of pulverized fuel particles. Combustion rates were estimated from the ignition temperatures and were compared with rates determined experimentally using a fixed-bed reactor, DTG, and an entrained-flow reactor. Three Australian coals, two chars prepared from these coals and a petroleum coke were used. Coal rank and particle size were found to influence the ignition temperatures of the coal and char particles. However, these effects were reduced at high oxygen concentrations. In pure oxygen, the ignition temperatures of the chars and their parent coals were similar. Heterogeneous and homogeneous ignition theories indicated that at low O concentrations ignition was controlled by a homogeneous mechanism, whereas at high O concentrations heterogeneous ignition became dominant. The combustion rates of the chars determined by the four techniques were compared at an oxygen partial pressure of 10.1 kPa. The results of the fixed-bed, DTG and entrained flow experiments were consistent with each other and spanned the range of kinetic control from regime I at low temperature (fixed bed) to regime II at high temperature (entrained flow). The drop-tube experiments indicated consistently higher combustion rates than did the other techniques. The pulse ignition measurements therefore, while providing a valid means of characterizing coal and char ignition behaviour, result in overestimation of the char combustion rate

Self-Assembly of Peptide Nanotubes in an Organic Solvent

The self-assembly of a modified fragment of the amyloid β peptide, based on sequence Aβ(16-20), KLVFF, extended to give AAKLVFF is studied in methanol. Self-assembly into peptide nanotubes is observed, as confirmed by electron microscopy and small-angle X-ray scattering. The secondary structure of the peptide is probed by FTIR and circular dichroism, and UV/visible spectroscopy provides evidence for the important role of aromatic interactions between phenylalanine residues in driving β-sheet self-assembly. The β-sheets wrap helically to form the nanotubes, the nanotube wall comprising four wrapped β-sheets. At higher concentration, the peptide nanotubes form a nematic phase that exhibits spontaneous flow alignment as observed by small-angle neutron scattering