8,866 research outputs found

    Investigations into the molecular effects of single nucleotide polymorphism

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    Objectives: DNA sequences are very rich in short repeats and their pattern can be altered by point mutations. We wanted to investigate the effect of single nucleotide polymorphism (SNP) on the pattern of short DNA repeats and its biological consequences. Methods: Analysis of the pattern of short DNA repeats of the Thy-1 sequence with and without SNP. Searching for DNA-binding factors in any region of significance. Results: Comparing the pattern of short repeats in the Thy-1 gene sequences of Turkish patients with ataxia telangiectasia (AT) with the `wild type' sequence from the DNA database, we identified a missing 8-bp repeat element due to an SNP in position 1271 (intron II) in AT-DNA sequences. Only the mutated sequence had the potential for the formation of a stem loop in DNA or pre-mRNA. In super-shift experiments we found that DNA oligomers covering the area of this SNP formed a complex with proteins amongst which we identified the proliferating cell nuclear antigen (PCNA) protein. Conclusion: SNPs have the potential to alter DNA or pre-mRNA conformation. Although no SNP-depeding formation of the DNA-protein complex was evident, future investigations could reveal differential molecular mechanisms of cellular regulation. Copyright (C) 2001 S. Karger AG, Basel

    Reply to Comment on "Critical analysis of a variational method used to describe molecular electron transport"

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    We show that the failure of the Delaney-Greer (DG) variational ansatz for transport demonstrated by us in Phys.\ Rev.\ B {\bf 80}, 165301 (2009) (I) is not related to an unsuitable constraint that prevents a broken time-reversal symmetry or to real orbitals, as DG incorrectly claim. The complex orbitals suggested by them as a way-out solution merely represent a particular case of the general case considered by us in I, which do not in the least affect our conclusion.Comment: Manuscript as submitted to Phys. Rev. B on 30 November 2010. Sections VII, VIII, and IX present significant details, which enlarge the analysis of the published versio

    An Account of the Loss of the Country Ship Forbes and Frazer Sinclair, Her Late Commander

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    This paper reports on the life of the English Country trader Captain Frazer Sinclair leading up to and following the loss of the Forbes in the Karimata Strait in 1806. It examines the adventure and tenuous times of trading around the Indonesian archipelago after the fall of the VOC and subsequent transfer to the British. Included are the details of Captain Sinclair\u27s trading history, multiple prizes as a privateer, and shipwrecks

    Rapidity dependence of entropy production in proton- and nucleus-induced reactions on heavy nuclei

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    The entropy of hot nuclear systems is deduced from the mass distribution of fragments emitted from high energy proton- and nucleus-induced reactions via a quantum statistical model. It is found that the entropy per baryon, S/A, of intermediate rapidity ("participant") fragments is higher than the entropy of target rapidity ("spectator") fragments. The spectator fragments exhibit S/A values of ≅ 1.8 independent of the projectile energy from 30 MeV/nucleon up to 350 GeV. This value of the entropy coincides with the entropy at which nuclear matter becomes unbound

    Mach Cones and Hydrodynamic Flow: Probing Big Bang Matter in the Laboratory

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    A critical discussion of the present signals for the phase transition to quark-gluon plasma (QGP) is given. Since hadronic rescattering models predict much larger flow than observed from 1 to 50 A GeV laboratory bombarding energies, this observation is interpreted as potential evidence for a first-order phase transition at high baryon density. A detailed discussion of the collective flow as a barometer for the equation of state (EoS) of hot dense matter at RHIC follows. Here, hadronic rescattering models can explain < 30 % of the observed elliptic flow v_2 for pT>2p_T > 2 GeV/c. This is interpreted as an evidence for the production of superdense matter at RHIC. The connection of v_2 to jet suppression is examined. A study of Mach shocks generated by fast partonic jets propagating through the QGP is given. The main goal is to take into account different types of collective motion during the formation and evolution of this matter. A significant deformation of Mach shocks in central Au+Au collisions at RHIC and LHC energies as compared to the case of jet propagation in a static medium is predicted. A new hydrodynamical study of jet energy loss is presented.Comment: 18 pages, 12 figures, presented at the IWCF 2006, Nov. 21-24, Hangzhou, Chin

    Information gain versus state disturbance for a single qubit

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    The trade-off between the information gain and the state disturbance is derived for quantum operations on a single qubit prepared in a uniformly distributed pure state. The derivation is valid for a class of measures quantifying the state disturbance and the information gain which satisfy certain invariance conditions. This class includes in particular the Shannon entropy versus the operation fidelity. The central role in the derivation is played by efficient quantum operations, which leave the system in a pure output state for any measurement outcome. It is pointed out that the optimality of efficient quantum operations among those inducing a given operator-valued measure is related to Davies' characterization of convex invariant functions on hermitian operators.Comment: 17 pages, LaTeX, osid.sty. Substantially expanded and generalize

    Report and preliminary results of METEOR-Cruise M 41/1, MĂĄlaga - Libreville, 13.2.-15.3.1998 with partial results of METEOR CRUISE 41/2 Libreville-VitĂłria, 18.03.1998-15.04.1998

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    The witness seminar ”The rise and expansion of IT consulting, 1964–1985” took place at The National Museum of Science and Technology in Stockholm on 1 April 2008 and was led by Gunnar Hesse. The panel consisted of representatives of many of the pioneers in Swedish IT consulting, including Lars Irstad, who founded the industry leader Programator in 1964; Lars SpĂ„ngberg who founded RIAB as an offshoot of the Federation of Swedish Industry in 1968; Thord Wilkne, one of two founders of WM-data in 1969; Göran Garvner who founded Modulföretagen in 1972; Per Olof Persson, a leading figure in Statskonsult, the state-owned firm that was the biggest IT consultancy in Sweden in the 1970s; Kaj Green, the first CEO of Cap Gemini Sweden; Leif Nobel, CEO of Data Logic from 1979, and Hans G. Wahlberg, one of the founders of Enator in 1977. The seminar was divided in three parts. The first dealt with the period of early entrepreneurship up to c. 1975. It was agreed that there was no shortage of demand for consulting services and that the main challenge consisted in recruiting skilled personnel and managing them. The second part dealt with the expansion that set in from the mid-1970s. Here it was agreed that the management of knowledge workers still constituted the single biggest challenge, followed by the need to establish consistency in method. At this point a divergence in business strategy can be seen. WM-data became a provider of American standard applications in order to tie the customer base more tightly. Programator were successful in the minicomputing market and established joint ventures with several large companies, in effect taking over their IT departments. Enator moved up the value chain and aimed at integrating management consulting and IT consulting. By 1985 all the major companies were listed at the stock exchange and the industry may be described as well-established
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