1,957 research outputs found

    Anthrazykline und HerceptinÂź als neue Therapieoption beim metastasierten Mammakarzinom

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    Single-agent treatment with the humanized monoclonal antibody trastuzumab (herceptin) has shown remarkable activity in patients with metastatic breast cancer overexpressing the HER-2/neu proto-oncogen. Further significant advances could be achieved with the combined use of herceptin and paclitaxel or doxorubicin/cyclophosphamide. However, cardiotoxicity remains a significant and thus far unresolved problem of the herceptin-doxo-rubicin combination. Thus, several studies have recently been initiated to identify equally effective but less toxic first-line regimens. Epirubicin, the taxanes paclitaxel and docetaxel, Navelbine(R), cisplatin, and Caelyx(R), a liposomal encapsulated formulation of doxorubicin, were selected for combination with herceptin in these studies because the appeared the most promising agents

    PALMA: Perfect Alignments using Large Margin Algorithms

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    Despite many years of research on how to properly align sequences in the presence of sequencing errors, alternative splicing and micro-exons, the correct alignment of mRNA sequences to genomic DNA is still a challenging task. We present a novel approach based on large margin learning that combines kernel based splice site predictions with common sequence alignment techniques. By solving a convex optimization problem, our algorithm -- called PALMA -- tunes the parameters of the model such that the true alignment scores higher than all other alignments. In an experimental study on the alignments of mRNAs containing artificially generated micro-exons, we show that our algorithm drastically outperforms all other methods: It perfectly aligns all 4358 sequences on an hold-out set, while the best other method misaligns at least 90 of them. Moreover, our algorithm is very robust against noise in the query sequence: when deleting, inserting, or mutating up to 50 of the query sequence, it still aligns 95 of all sequences correctly, while other methods achieve less than 36 accuracy. For datasets, additional results and a stand-alone alignment tool see http://www.fml.mpg.de/raetsch/projects/palma

    Lifshitz-point critical behaviour to O(ϔ2){\boldsymbol{O(\epsilon^2)}}

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    We comment on a recent letter by L. C. de Albuquerque and M. M. Leite (J. Phys. A: Math. Gen. 34 (2001) L327-L332), in which results to second order in Ï”=4−d+m2\epsilon=4-d+\frac{m}{2} were presented for the critical exponents ÎœL2\nu_{{\mathrm{L}}2}, ηL2\eta_{{\mathrm{L}}2} and ÎłL2\gamma_{{\mathrm{L}}2} of d-dimensional systems at m-axial Lifshitz points. We point out that their results are at variance with ours. The discrepancy is due to their incorrect computation of momentum-space integrals. Their speculation that the field-theoretic renormalization group approach, if performed in position space, might give results different from when it is performed in momentum space is refuted.Comment: Latex file, uses the included iop stylefiles; Uses the texdraw package to generate included figure

    Global Mutual Fund Industry Comparisons: Canada, The United Kingdom And The United States

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    The concept of mutual funds is older than many believe, originating in Holland over 230 years ago.  Through the years, mutual funds have evolved by allowing investors to invest their capital in various venues.  The structure of mutual funds in Canada, the United Kingdom, and the United States possess similar configurations.  The majority of funds in all three nations are invested in the equity market.  Although the structure may be the same, the size in terms of assets varies by these three countries.  This is not the only difference though; the expense ratio is greatly differentiated, dramatically affecting the amount of return that the investor will anticipate over time.  Assuming identical returns, the authors illustrate that over a hypothetical ten-year time period, your funds would grow the most in the United States, followed by the United Kingdom and finally Canada.  This analysis assumes comparable contemporary expense ratios of 1.4% for the United States, 1.63% for the United Kingdom, and 2.1% for Canada.  In addition, we make the assumption that these comparison countries are having investors procure funds in no-load mutual funds

    The role of infrared divergence for decoherence

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    Continuous and discrete superselection rules induced by the interaction with the environment are investigated for a class of exactly soluble Hamiltonian models. The environment is given by a Boson field. Stable superselection sectors emerge if and only if the low frequences dominate and the ground state of the Boson field disappears due to infrared divergence. The models allow uniform estimates of all transition matrix elements between different superselection sectors.Comment: 11 pages, extended and simplified proo

    Non-Commutative Complete Mellin Representation for Feynman Amplitudes

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    We extend the complete Mellin (CM) representation of Feynman amplitudes to the non-commutative quantum field theories. This representation is a versatile tool. It provides a quick proof of meromorphy of Feynman amplitudes in parameters such as the dimension of space-time. In particular it paves the road for the dimensional renormalization of these theories. This complete Mellin representation also allows the study of asymptotic behavior under rescaling of arbitrary subsets of external invariants of any Feynman amplitude.Comment: 14 pages, no figur

    Subtraction at NNLO

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    We propose a framework for the implementation of a subtraction formalism at NNLO in QCD, based on an observable- and process-independent cancellation of infrared singularities. As a first simple application, we present the calculation of the contribution to the e+e- dijet cross section proportional to C_F T_RComment: 42 pages Latex; 7 figures included. Modifications to the text, and references added; the results are unchange

    Decay of Loschmidt Echo Enhanced by Quantum Criticality

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    We study the transition of a quantum system SS from a pure state to a mixed one, which is induced by the quantum criticality of the surrounding system EE coupled to it. To characterize this transition quantitatively, we carefully examine the behavior of the Loschmidt echo (LE) of EE modelled as an Ising model in a transverse field, which behaves as a measuring apparatus in quantum measurement. It is found that the quantum critical behavior of EE strongly affects its capability of enhancing the decay of LE: near the critical value of the transverse field entailing the happening of quantum phase transition, the off-diagonal elements of the reduced density matrix describing SS vanish sharply.Comment: 4 pages, 3 figure

    Is there a no-go theorem for superradiant quantum phase transitions in cavity and circuit QED ?

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    In cavity quantum electrodynamics (QED), the interaction between an atomic transition and the cavity field is measured by the vacuum Rabi frequency Ω0\Omega_0. The analogous term "circuit QED" has been introduced for Josephson junctions, because superconducting circuits behave as artificial atoms coupled to the bosonic field of a resonator. In the regime with Ω0\Omega_0 comparable to the two-level transition frequency, "superradiant" quantum phase transitions for the cavity vacuum have been predicted, e.g. within the Dicke model. Here, we prove that if the time-independent light-matter Hamiltonian is considered, a superradiant quantum critical point is forbidden for electric dipole atomic transitions due to the oscillator strength sum rule. In circuit QED, the capacitive coupling is analogous to the electric dipole one: yet, such no-go property can be circumvented by Cooper pair boxes capacitively coupled to a resonator, due to their peculiar Hilbert space topology and a violation of the corresponding sum rule

    Systematic Implementation of Implicit Regularization for Multi-Loop Feynman Diagrams

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    Implicit Regularization (IReg) is a candidate to become an invariant framework in momentum space to perform Feynman diagram calculations to arbitrary loop order. In this work we present a systematic implementation of our method that automatically displays the terms to be subtracted by Bogoliubov's recursion formula. Therefore, we achieve a twofold objective: we show that the IReg program respects unitarity, locality and Lorentz invariance and we show that our method is consistent since we are able to display the divergent content of a multi-loop amplitude in a well defined set of basic divergent integrals in one loop momentum only which is the essence of IReg. Moreover, we conjecture that momentum routing invariance in the loops, which has been shown to be connected with gauge symmetry, is a fundamental symmetry of any Feynman diagram in a renormalizable quantum field theory
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