Mutual information for examining correlations in DNA

This paper examines two methods for finding whether long-range correlations exist in DNA: a fractal measure and a mutual information technique. We evaluate the performance and implications of these methods in detail. In particular we explore their use comparing DNA sequences from a variety of sources. Using software for performing in silico mutations, we also consider evolutionary events leading to long range correlations and analyse these correlations using the techniques presented. Comparisons are made between these virtual sequences, randomly generated sequences, and real sequences. We also explore correlations in chromosomes from different species.Comment: 8 pages, 3 figure

Guidance, flight mechanics and trajectory optimization. Volume 1 - Coordinate systems and time measure

Coordinate measuring system for flight control, and trajectory optimizatio

Stage-Specific Timing of the microRNA Regulation of \u3cem\u3elin-28\u3c/em\u3e by the Heterochronic Gene \u3cem\u3elin-14\u3c/em\u3e in \u3cem\u3eCaenorhabditis elegans\u3c/em\u3e

In normal development, the order and synchrony of diverse developmental events must be explicitly controlled. In the nematode Caenorhabditis elegans, the timing of larval events is regulated by hierarchy of proteins and microRNAs (miRNAs) known as the heterochronic pathway. These regulators are organized in feedforward and feedback interactions to form a robust mechanism for specifying the timing and execution of cell fates at successive stages. One member of this pathway is the RNA binding protein LIN-28, which promotes pluripotency and cell fate decisions in successive stages. Two genetic circuits control LIN-28 abundance: it is negatively regulated by the miRNA lin-4, and positively regulated by the transcription factor LIN-14 through a mechanism that was previously unknown. In this report, we used animals that lack lin-4 to elucidate LIN-14’s activity in this circuit. We demonstrate that three let-7 family miRNAs—miR-48, miR-84, and miR-241—inhibit lin-28 expression. Furthermore, we show genetically that these miRNAs act between lin-14 and lin-28, and that they comprise the pathway by which lin-14 positively regulates lin-28. We also show that the lin-4 family member mir-237, also regulates early cell fates. Finally, we show that the expression of these miRNAs is directly inhibited by lin-14 activity, making them the first known targets of lin-14 that act in the heterochronic pathway

Transport of a colloidal particle driven across a temporally oscillating optical potential energy landscape

A colloidal particle is driven across a temporally oscillating one-dimensional optical potential energy landscape and its particle motion is analysed. Different modes of dynamic mode locking are observed and are confirmed with the use of phase portraits. The effect of the oscillation frequency on the mode locked step width is addressed and the results are discussed in light of a high-frequency theory and compared to simulations. Furthermore, the influence of the coupling between the particle and the optical landscape on mode locking is probed by increasing the maximum depth of the optical landscape. Stronger coupling is seen to increase the width of mode locked steps. Finally, transport across the temporally oscillating landscape is studied by measuring the effective diffusion coefficient of a mobile particle, which is seen to be highly sensitive to the driving velocity and mode locking

Transition from Quantum to Classical Information in a Superfluid

Whereas the entropy of any deterministic classical system described by a principle of least action is zero, one can assign a "quantum information" to quantum mechanical degree of freedom equal to Hausdorff area of the deviation from a classical path. This raises the question whether superfluids carry quantum information. We show that in general the transition from the classical to quantum behavior depends on the probing length scale, and occurs for microscopic length scales, except when the interactions between the particles are very weak. This transition explains why, on macroscopic length scales, physics is described by classical equations.Comment: 11 pages, 4 figure

Search for lepton-flavour-violating H → μτ decays of the Higgs boson with the ATLAS detector

A direct search for lepton-flavour-violating H → μτ decays of the recently discovered Higgs boson with the ATLAS detector at the LHC is presented. The analysis is performed in the H → μτ had channel, where τ had is a hadronically decaying τ -lepton. The search is based on the data sample of proton-proton collisions collected by the ATLAS experiment corresponding to an integrated luminosity of 20.3 fb−1 at a centre-of-mass energy of s√=8s=8 TeV. No statistically significant excess of data over the predicted background is observed. The observed (expected) 95% confidence-level upper limit on the branching fraction, Br(H → μτ ), is 1.85% (1.24%)

Z boson production in p + Pb collisions at √ s NN = 5.02 TeV measured with the ATLAS detector

The ATLAS Collaboration measures the inclusive production of Z bosons via their decays into electron and muon pairs in p+Pb collisions at √sNN=5.02TeV at the Large Hadron Collider. The measurements are made using data corresponding to integrated luminosities of 29.4 and 28.1 nb−1 for Z→ee and Z→μμ, respectively. The results from the two channels are consistent and combined to obtain a cross section times the Z→ℓℓ branching ratio, integrated over the rapidity region ∣∣y∗Z|<3.5, of 139.8±4.8(statistical)±6.2(systematic)±3.8 (luminosity) nb. Differential cross sections are presented as functions of the Z boson rapidity and transverse momentum and compared with models based on parton distributions both with and without nuclear corrections. The centrality dependence of Z boson production in p+Pb collisions is measured and analyzed within the framework of a standard Glauber model and the model's extension for fluctuations of the underlying nucleon-nucleon scattering cross section

Centrality and rapidity dependence of inclusive jet production in √sNN = 5.02 TeV proton-lead collisions with the ATLAS detector

Measurements of the centrality and rapidity dependence of inclusive jet production in √sNN=5.02TeV proton–lead (p +Pb) collisions and the jet cross-section in √s=2.76TeV proton–proton collisions are presented. These quantities are measured in datasets corresponding to an integrated luminosity of 27.8nb−1and 4.0pb−1, respectively, recorded with the ATLAS detector at the Large Hadron Collider in2013. The p +Pbcollision centrality was characterised using the total transverse energy measured in the pseudorapidity interval −4.9 <η<−3.2in the direction of the lead beam. Results are presented for the double-differential per-collision yields as a function of jet rapidity and transverse momentum (pT) for minimum-bias and centrality-selected p +Pbcollisions, and are compared to the jet rate from the geometric expectation. The total jet yield in minimum-bias events is slightly enhanced above the expectation in a pT-dependent manner but is consistent with the expectation within uncertainties. The ratios of jet spectra from different centrality selections show a strong modification of jet production at all pTat forward rapidities and for large pTat mid-rapidity, which manifests as a suppression of the jet yield in central events and an enhancement in peripheral events. These effects imply that the factorisation between hard and soft processes is violated at an unexpected level in proton–nucleus collisions. Furthermore, the modifications at forward rapidities are found to be a function of the total jet energy only, implying that the violations may have a simple dependence on the hard parton–parton kinematics

Searches for Higgs boson pair production in the hh → bbττ, γγWW*, γγbb, bbbb channels with the ATLAS detector

We present the calculation of the hyperon forward spin polarizability γ0 using manifestly Lorentz-covariant baryon chiral perturbation theory including the intermediate contribution of the spin-3/2 states. As at the considered order the extraction of γ0 is a pure prediction of chiral perturbation theory, the obtained values are a good test for this theory. After including explicitly the decuplet states, our SU(2) results have a very good agreement with the experimental data and we extend our framework to SU(3) to give predictions for the hyperons’ γ0 values. Prominent are the Σ− and Ξ− baryons as their photon transition to the decuplet is forbidden in SU(3) symmetry and therefore they are not sensitive to the explicit inclusion of the decuplet in the theory

Measurement of the production of neighbouring jets in lead-lead collisions at √sNN = 2.76 TeV with the ATLAS detector

This Letter presents measurements of correlated production of nearby jets in Pb+Pb collisions at View the MathML source using the ATLAS detector at the Large Hadron Collider. The measurement was performed using 0.14 nb−1 of data recorded in 2011. The production of correlated jet pairs was quantified using the rate, RΔR, of “neighbouring” jets that accompany “test” jets within a given range of angular distance, ΔR , in the pseudorapidity–azimuthal angle plane. The jets were measured in the ATLAS calorimeter and were reconstructed using the anti-kt algorithm with radius parameters d=0.2, 0.3, and 0.4. RΔR was measured in different Pb+Pb collision centrality bins, characterized by the total transverse energy measured in the forward calorimeters. A centrality dependence of RΔR is observed for all three jet radii with RΔR found to be lower in central collisions than in peripheral collisions. The ratios formed by the RΔR values in different centrality bins and the values in the 40–80% centrality bin are presented