1,961 research outputs found
Anthrazykline und HerceptinÂź als neue Therapieoption beim metastasierten Mammakarzinom
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
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
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 were presented for the critical
exponents , and
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
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
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
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
Decay of Loschmidt Echo Enhanced by Quantum Criticality
We study the transition of a quantum system from a pure state to a mixed
one, which is induced by the quantum criticality of the surrounding system
coupled to it. To characterize this transition quantitatively, we carefully
examine the behavior of the Loschmidt echo (LE) of 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 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 vanish
sharply.Comment: 4 pages, 3 figure
Subtraction at NNLO
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
Is there a no-go theorem for superradiant quantum phase transitions in cavity and circuit QED ?
In cavity quantum electrodynamics (QED), the interaction between an atomic
transition and the cavity field is measured by the vacuum Rabi frequency
. 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 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
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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