The MEGAPIE-TEST Project

The goals of the MEGAPIE initiative are to design, build and operate a 1MW heavy liquid metal target. The first step towards the realization of the MEGAPIE target was the feasibility studies, which outlined the entire project. Contextually to the feasibility studies the conceptual design phase started with the establishment of R&D working groups assisting the design and validation of both the target and its ancillary systems. In this framework the EU project MEGAPIE-TEST has been structured in three work packages with tasks concerning the finalization of the engineering design, the components and subsystem testing, the integral test and the first irradiation period. The MEGAPIE-TEST consortium is composed by the 14 partners: FZK, PSI, CEA, ENEA, SCK-CEN, CNRS /IDFE, IN2P3, LMPGM, EMN, ISMRA, UNIV-NANTES, U-PSUDXI, USTL. Currently the engineering design of the target has been finalized, its manufacturing has been launched and the design activities on the ancillary systems were almost completed. R&D activities in the fields of materials, thermal – hydraulics, structural mechanics, neutronic and nuclear assessment and liquid metal technologies were performed in order to assist specific design issues. Some Subsystem and component tests were also performed and the preparation of the integral test is an ongoing activity

mTORC2-AKT signaling to ATP-citrate lyase drives brown adipogenesis and de novo lipogenesis

mTORC2 phosphorylates AKT in a hydrophobic motif site that is a biomarker of insulin sensitivity. In brown adipocytes, mTORC2 regulates glucose and lipid metabolism, however the mechanism has been unclear because downstream AKT signaling appears unaffected by mTORC2 loss. Here, by applying immunoblotting, targeted phosphoproteomics and metabolite profiling, we identify ATP-citrate lyase (ACLY) as a distinctly mTORC2-sensitive AKT substrate in brown preadipocytes. mTORC2 appears dispensable for most other AKT actions examined, indicating a previously unappreciated selectivity in mTORC2-AKT signaling. Rescue experiments suggest brown preadipocytes require the mTORC2/AKT/ACLY pathway to induce PPAR-gamma and establish the epigenetic landscape during differentiation. Evidence in mature brown adipocytes also suggests mTORC2 acts through ACLY to increase carbohydrate response element binding protein (ChREBP) activity, histone acetylation, and gluco-lipogenic gene expression. Substrate utilization studies additionally implicate mTORC2 in promoting acetyl-CoA synthesis from acetate through acetyl-CoA synthetase 2 (ACSS2). These data suggest that a principal mTORC2 action is controlling nuclear-cytoplasmic acetyl-CoA synthesis

Groundwater Control in Tunneling: Executive Summary

DOT-FH-11-9516This Executive Summary briefly describes a three-volume report on Groundwater Control During Tunneling and in Completed Tunnels

Accurate Prediction of Inducible Transcription Factor Binding Intensities In Vivo

DNA sequence and local chromatin landscape act jointly to determine transcription factor (TF) binding intensity profiles. To disentangle these influences, we developed an experimental approach, called protein/DNA binding followed by high-throughput sequencing (PB–seq), that allows the binding energy landscape to be characterized genome-wide in the absence of chromatin. We applied our methods to the Drosophila Heat Shock Factor (HSF), which inducibly binds a target DNA sequence element (HSE) following heat shock stress. PB–seq involves incubating sheared naked genomic DNA with recombinant HSF, partitioning the HSF–bound and HSF–free DNA, and then detecting HSF–bound DNA by high-throughput sequencing. We compared PB–seq binding profiles with ones observed in vivo by ChIP–seq and developed statistical models to predict the observed departures from idealized binding patterns based on covariates describing the local chromatin environment. We found that DNase I hypersensitivity and tetra-acetylation of H4 were the most influential covariates in predicting changes in HSF binding affinity. We also investigated the extent to which DNA accessibility, as measured by digital DNase I footprinting data, could be predicted from MNase–seq data and the ChIP–chip profiles for many histone modifications and TFs, and found GAGA element associated factor (GAF), tetra-acetylation of H4, and H4K16 acetylation to be the most predictive covariates. Lastly, we generated an unbiased model of HSF binding sequences, which revealed distinct biophysical properties of the HSF/HSE interaction and a previously unrecognized substructure within the HSE. These findings provide new insights into the interplay between the genomic sequence and the chromatin landscape in determining transcription factor binding intensity

Measurements of Dihadron Correlations Relative to the Event Plane in Au+Au Collisions at sNN=200\sqrt{s_{NN}}=200 GeV

Dihadron azimuthal correlations containing a high transverse momentum (\pt) trigger particle are sensitive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium, i.e. jet-quenching. Previous measurements revealed a strong modification to dihadron azimuthal correlations in Au+Au collisions with respect to \pp\ and \dAu\ collisions. The modification increases with the collision centrality, suggesting a path-length dependence to the jet-quenching effect. This paper reports STAR measurements of dihadron azimuthal correlations in mid-central (20-60\%) Au+Au collisions at \snn=200~GeV as a function of the trigger particle's azimuthal angle relative to the event plane, \phis=|\phit-\psiEP|. The azimuthal correlation is studied as a function of both the trigger and associated particle \pt. The subtractions of the combinatorial background and anisotropic flow, assuming Zero Yield At Minimum (\zyam), are described. The away-side correlation is strongly modified, and the modification varies with \phis, which is expected to be related to the path-length that the away-side parton traverses. The pseudo-rapidity (\deta) dependence of the near-side correlation, sensitive to long range \deta correlations (the ridge), is also investigated. The ridge and jet-like components of the near-side correlation are studied as a function of \phis. The ridge appears to drop with increasing \phis while the jet-like component remains approximately constant. ...Comment: 50 pages, 39 figures, 6 table

Studies of di-jet survival and surface emission bias in Au+Au collisions via angular correlations with respect to back-to-back leading hadrons

We report first results from an analysis based on a new multi-hadron correlation technique, exploring jet-medium interactions and di-jet surface emission bias at RHIC. Pairs of back-to-back high transverse momentum hadrons are used for triggers to study associated hadron distributions. In contrast with two- and three-particle correlations with a single trigger with similar kinematic selections, the associated hadron distribution of both trigger sides reveals no modification in either relative pseudo-rapidity or relative azimuthal angle from d+Au to central Au+Au collisions. We determine associated hadron yields and spectra as well as production rates for such correlated back-to-back triggers to gain additional insights on medium properties.Comment: By the STAR Collaboration. 6 pages, 2 figure

Why alternative teenagers self-harm: exploring the link between non-suicidal self-injury, attempted suicide and adolescent identity

Background: The term ‘self-harm’ encompasses both attempted suicide and non-suicidal self-injury (NSSI). Specific adolescent subpopulations such as ethnic or sexual minorities, and more controversially, those who identify as ‘Alternative’ (Goth, Emo) have been proposed as being more likely to self-harm, while other groups such as ‘Jocks’ are linked with protective coping behaviours (for example exercise). NSSI has autonomic (it reduces negative emotions) and social (it communicates distress or facilitates group ‘bonding’) functions. This study explores the links between such aspects of self-harm, primarily NSSI, and youth subculture.<p></p> Methods: An anonymous survey was carried out of 452 15 year old German school students. Measures included: identification with different youth cultures, i.e. Alternative (Goth, Emo, Punk), Nerd (academic) or Jock (athletic); social background, e.g. socioeconomic status; and experience of victimisation. Self-harm (suicide and NSSI) was assessed using Self-harm Behavior Questionnaire and the Functional Assessment of Self-Mutilation (FASM).<p></p> Results: An “Alternative” identity was directly (r ≈ 0.3) and a “Jock” identity inversely (r ≈ -0.1) correlated with self-harm. “Alternative” teenagers self-injured more frequently (NSSI 45.5% vs. 18.8%), repeatedly self-injured, and were 4–8 times more likely to attempt suicide (even after adjusting for social background) than their non-Alternative peers. They were also more likely to self-injure for autonomic, communicative and social reasons than other adolescents.<p></p> Conclusions: About half of ‘Alternative’ adolescents’ self-injure, primarily to regulate emotions and communicate distress. However, a minority self-injure to reinforce their group identity, i.e. ‘To feel more a part of a group’

Observation of the antimatter helium-4 nucleus

High-energy nuclear collisions create an energy density similar to that of the universe microseconds after the Big Bang, and in both cases, matter and antimatter are formed with comparable abundance. However, the relatively short-lived expansion in nuclear collisions allows antimatter to decouple quickly from matter, and avoid annihilation. Thus, a high energy accelerator of heavy nuclei is an efficient means of producing and studying antimatter. The antimatter helium-4 nucleus ($^4\bar{He}$), also known as the anti-{\alpha} ($\bar{\alpha}$), consists of two antiprotons and two antineutrons (baryon number B=-4). It has not been observed previously, although the {\alpha} particle was identified a century ago by Rutherford and is present in cosmic radiation at the 10% level. Antimatter nuclei with B < -1 have been observed only as rare products of interactions at particle accelerators, where the rate of antinucleus production in high-energy collisions decreases by about 1000 with each additional antinucleon. We present the observation of the antimatter helium-4 nucleus, the heaviest observed antinucleus. In total 18 $^4\bar{He}$ counts were detected at the STAR experiment at RHIC in 10$^9$ recorded Au+Au collisions at center-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon pair. The yield is consistent with expectations from thermodynamic and coalescent nucleosynthesis models, which has implications beyond nuclear physics.Comment: 19 pages, 4 figures. Submitted to Nature. Under media embarg

Field-tuned Collapse of an Orbital Ordered and Spin-polarized State: Colossal Magnetoresistance in Bilayered Ruthenate

Ca3Ru2O7 with a Mott-like transition at 48 K features different in-plane anisotropies of magnetization and magnetoresistance. Applying magnetic field along the magnetic easy-axis precipitates a spin-polarized state via a first-order metamagnetic transition, but does not lead to a full suppression of the Mott state, whereas applying magnetic field along the magnetic hard axis does, causing a resistivity reduction of three orders of magnitude. The colossal magnetoresistivity is attributed to the collapse of the orbital ordered and spin-polarized state. Evidence for a density wave is also presented.Comment: 10 pages plus 4 figure

An Experimental Exploration of the QCD Phase Diagram: The Search for the Critical Point and the Onset of De-confinement

The QCD phase diagram lies at the heart of what the RHIC Physics Program is all about. While RHIC has been operating very successfully at or close to its maximum energy for almost a decade, it has become clear that this collider can also be operated at lower energies down to 5 GeV without extensive upgrades. An exploration of the full region of beam energies available at the RHIC facility is imperative. The STAR detector, due to its large uniform acceptance and excellent particle identification capabilities, is uniquely positioned to carry out this program in depth and detail. The first exploratory beam energy scan (BES) run at RHIC took place in 2010 (Run 10), since several STAR upgrades, most importantly a full barrel Time of Flight detector, are now completed which add new capabilities important for the interesting physics at BES energies. In this document we discuss current proposed measurements, with estimations of the accuracy of the measurements given an assumed event count at each beam energy.Comment: 59 pages, 78 figure