The greatest catch:Big game fishing for mRNA-bound proteins

Purification of proteins cross-linked to mRNAs has identified 800 mRNA-binding proteins and their characteristics

Asymptotic Behavior of the Correlator for Polyakov Loops

The asymptotic behavior of the correlator for Polyakov loop operators separated by a large distance $R$ is determined for high temperature QCD. It is dominated by nonperturbative effects related to the exchange of magnetostatic gluons. To analyze the asymptotic behavior, the problem is formulated in terms of the effective field theory of QCD in 3 space dimensions. The Polyakov loop operator is expanded in terms of local gauge-invariant operators constructed out of the magnetostatic gauge field, with coefficients that can be calculated using resummed perturbation theory. The asymptotic behavior of the correlator is $\exp(-MR)/R$, where $M$ is the mass of the lowest-lying glueball in $(2+1)$-dimensional QCD. This result implies that existing lattice calculations of the Polyakov loop correlator at the highest temperatures available do not probe the true asymptotic region in $R$.Comment: 10 pages, NUHEP-TH-94-2

The transcriptional landscape of endogenous retroelements delineates esophageal adenocarcinoma subtypes

Most cancer types exhibit aberrant transcriptional activity, including derepression of retrotransposable elements (RTEs). However, the degree, specificity and potential consequences of RTE transcriptional activation may differ substantially among cancer types and subtypes. Representing one extreme of the spectrum, we characterize the transcriptional activity of RTEs in cohorts of esophageal adenocarcinoma (EAC) and its precursor Barrett's esophagus (BE) from the OCCAMS (Oesophageal Cancer Clinical and Molecular Stratification) consortium, and from TCGA (The Cancer Genome Atlas). We found exceptionally high RTE inclusion in the EAC transcriptome, driven primarily by transcription of genes incorporating intronic or adjacent RTEs, rather than by autonomous RTE transcription. Nevertheless, numerous chimeric transcripts straddling RTEs and genes, and transcripts from stand-alone RTEs, particularly KLF5- and SOX9-controlled HERVH proviruses, were overexpressed specifically in EAC. Notably, incomplete mRNA splicing and EAC-characteristic intronic RTE inclusion was mirrored by relative loss of the respective fully-spliced, functional mRNA isoforms, consistent with compromised cellular fitness. Defective RNA splicing was linked with strong transcriptional activation of a HERVH provirus on Chr Xp22.32 and defined EAC subtypes with distinct molecular features and prognosis. Our study defines distinguishable RTE transcriptional profiles of EAC, reflecting distinct underlying processes and prognosis, thus providing a framework for targeted studies.</p

Pollution control and environmental monitoring efforts at DOE's Coal-Fired Flow Facility

Proof-of-Concept (POC) scale demonstration of such technology is currently being carried out at the US Department of Energy's (DOE's) Coal-Fired Flow Facility (CFFF), located at The University of Tennessee Space Institute (UTSI) in Tullahoma, Tennessee and at the Component Development and Integration Facility in Butte, Montana. The CFFF is dedicated to the evaluation of downstream (steam cycle) components and technology that may be considered for a full-scale MHD system. The objectives of the CFFF testing include the demonstration of various pollution control devices and techniques at a scale sufficient for future scale-up. The CFFF offers a unique test environment in which emissions control techniques can be developed and evaluated through emissions and environmental monitoring. Results thus far have demonstrated the ability of sulfur oxide (SO{sub x}), nitrogen oxide (NO{sub x}) and particulate emissions well below the New Source Performance Standards (NSPS). Regeneration of the potassium sulfate to produce sulfur-free compounds also has been demonstrated. The experimental program at the CFFF is now aimed at determining the optimum conditions for future commercial scale designs. Because of increased interests in Air Toxics, measurements of nitrous oxide (N{sub 2}O), a potential greenhouse gas, priority pollutants (inorganic as well as organics), and chlorine-containing species (Cl{sub 2} and HCl) are also included in our ongoing efforts. Environmental monitoring activities are being pursued to develop an environmental impact assessment data base. These include the use of three ambient air sites to determine the impacts of gaseous and particulate emissions, five lake water sites to determine impacts due to process water discharges and seven sites to collect terrestrial data on possible soil contamination and tree growth. In this paper, we will summarize the status of our ongoing environmental program. 16 refs., 15 figs., 3 tabs

Thermodynamics of lattice QCD with two light quark flavours on a 16^3 x 8 lattice II

We have extended our earlier simulations of the high temperature behaviour of lattice QCD with two light flavours of staggered quarks on a $16^3 \times 8$ lattice to lower quark mass (m_q=0.00625). The transition from hadronic matter to a quark-gluon plasma is observed at $6/g^2=5.49(2)$ corresponding to a temperature of $T_c \approx 140$MeV. We present measurements of observables which probe the nature of the quark-gluon plasma and serve to distinguish it from hadronic matter. Although the transition is quite abrupt, we have seen no indications that it is first order.Comment: 23 pages, RevteX, 6 encapsulated postscript figure

Quarkonium Suppression

I discuss quarkonium suppression in equilibriated strongly interacting matter. After a brief review of basic features of quarkonium production I discuss the application of recent lattice data on the heavy quark potential to the problem of quarkonium dissociation as well as the problem of direct lattice determination of quarkonium properties in finite temperature lattice QCD.Comment: Invited plenary talk presented on 4th International Conference on Physics and Astrophysics of Quark Gluon Plasma (ICPAQGP-2001), November 26-30, 2001, Jaipur; 12 pp, LaTeX, uses pramana.st

Heavy Quark Potentials in Quenched QCD at High Temperature

Heavy quark potentials are investigated at high temperatures. The temperature range covered by the analysis extends from $T$ values just below the deconfinement temperature up to about $4 T_c$ in the deconfined phase. We simulated the pure gauge sector of QCD on lattices with temporal extents of 4, 6 and 8 with spatial volumes of $32^3$. On the smallest lattice a tree level improved action was employed while in the other two cases the standard Wilson action was used. Below $T_c$ we find a temperature dependent logarithmic term contributing to the confinement potential and observe a string tension which decreases with rising temperature but retains a finite value at the deconfinement transition. Above $T_c$ the potential is Debye-screened, however simple perturbative predictions do not apply.Comment: 20 pages, 9 figure

Heavy Quark Free Energies and Screening in SU(2) Gauge Theory

We investigate the singlet, triplet and colour average heavy quark free energies in SU(2) pure gauge theory at various temperatures T. We focus on the long distance behaviour of the free energies, studying in particular the temperature dependence of the string tension and the screening masses. The results are qualitatively similar to the SU(3) scenario, except near the critical temperature Tc of the deconfining transition. Finally we test a recently proposed method to renormalize the Polyakov loop.Comment: 5 pages, 4 figures, contribution to the Proceedings of SEWM 2002 (Heidelberg

Phase structure of lattice QCD for general number of flavors

We investigate the phase structure of lattice QCD for the general number of flavors in the parameter space of gauge coupling constant and quark mass, employing the one-plaquette gauge action and the standard Wilson quark action. Performing a series of simulations for the number of flavors $N_F=6$--360 with degenerate-mass quarks, we find that when $N_F \ge 7$ there is a line of a bulk first order phase transition between the confined phase and a deconfined phase at a finite current quark mass in the strong coupling region and the intermediate coupling region. The massless quark line exists only in the deconfined phase. Based on these numerical results in the strong coupling limit and in the intermediate coupling region, we propose the following phase structure, depending on the number of flavors whose masses are less than $\Lambda_d$ which is the physical scale characterizing the phase transition in the weak coupling region: When $N_F \ge 17$, there is only a trivial IR fixed point and therefore the theory in the continuum limit is free. On the other hand, when $16 \ge N_F \ge 7$, there is a non-trivial IR fixed point and therefore the theory is non-trivial with anomalous dimensions, however, without quark confinement. Theories which satisfy both quark confinement and spontaneous chiral symmetry breaking in the continuum limit exist only for $N_F \le 6$.Comment: RevTeX, 20 pages, 43 PS figure

Damage Detection in Tensegrity using Interacting Particle-Ensemble Kalman Filter

The 10th EWSHM, originally scheduled for the first week of July 2020, is planned to be held the first week of July 2022 in Palermo.International audienceTensegrity structures form a special class of truss with dedicated cables and bars, that take tension and compression, respectively. To ensure equilibrium, the tensegrity members are required to be prestressed. Over prolonged usage, the cables may lose their prestress while bars may buckle, affecting the structural stiffness as well as its dynamic properties. The stiffness of tensegrities also vary with the load even in the absence of damage. This can potentially mask the effect of damage leading to a false impression of tensegrity health. This poses a major challenge in tensegrity health monitoring especially when the load is stochastic and unknown. Present study develops a vibration based output-only time-domain approach for monitoring the health of any tensegrity in the presence of uncertainties due to ambient force and measurement noise. An Interacting Particle Ensemble Kalman Filter (IPEnKF) has been used that can efficiently monitor tensegrity health from contaminated response data. IPEnKF combines a bank of Ensemble Kalman Filters to estimate response states while running within a Particle Filter envelop that estimates a set of location based health parameters. Further to make damage detection cheaper, strain responses are used as measurements. The efficiency of the proposed methodology has been demonstrated using numerical experiments performed on a simplex tensegrity