Cisplatin-based chemotherapy of testicular cancer - Two decades after a major breakthrough

Two decades ago the introduction of cisplatin-based combination chemotherapy has dramatically improved the prognosis of patients with metastatic testicular cancer, At present 3 cycles of cisplatin, etoposide and bleomycin are considered as standard treatment for good-risk metastatic disease. Outside of clinical trials patients in the intermediate and poor prognosis categories should receive 4 cycles of this standard regimen, Clinical trials currently evaluate the role of high-dose chemotherapy in first-line treatment of high-risk patients and in the salvage setting, Post-chemotherapy resection of tumor residuals remains an important part of therapy. Attention should be focused on long-term toxicity of therapy and the occurrence of late relapse

Replica Symmetry Breaking and the Kuhn-Tucker Cavity Method in simple and multilayer Perceptrons

Within a Kuhn-Tucker cavity method introduced in a former paper, we study optimal stability learning for situations, where in the replica formalism the replica symmetry may be broken, namely (i) the case of a simple perceptron above the critical loading, and (ii) the case of two-layer AND-perceptrons, if one learns with maximal stability. We find that the deviation of our cavity solution from the replica symmetric one in these cases is a clear indication of the necessity of replica symmetry breaking. In any case the cavity solution tends to underestimate the storage capabilities of the networks.Comment: 32 pages, LaTex Source with 9 .eps-files enclosed, accepted by J. Phys I (France

Phase Transitions for Random Walk Asymptotics on Free Products of Groups

Suppose we are given finitely generated groups $\Gamma_1,...,\Gamma_m$ equipped with irreducible random walks. Thereby we assume that the expansions of the corresponding Green functions at their radii of convergence contain only logarithmic or algebraic terms as singular terms up to sufficiently large order (except for some degenerate cases). We consider transient random walks on the free product {$\Gamma_1 \ast ... \ast\Gamma_m$} and give a complete classification of the possible asymptotic behaviour of the corresponding $n$-step return probabilities. They either inherit a law of the form $\varrho^{n\delta} n^{-\lambda_i} \log^{\kappa_i}n$ from one of the free factors $\Gamma_i$ or obey a $\varrho^{n\delta} n^{-3/2}$-law, where $\varrho<1$ is the corresponding spectral radius and $\delta$ is the period of the random walk. In addition, we determine the full range of the asymptotic behaviour in the case of nearest neighbour random walks on free products of the form $\Z^{d_1}\ast ... \ast \Z^{d_m}$. Moreover, we characterize the possible phase transitions of the non-exponential types $n^{-\lambda_i}\log^{\kappa_i}n$ in the case $\Gamma_1\ast\Gamma_2$.Comment: 32 page

Natural spanning trees of Zd are recurrent

AbstractWe show that the simple random walk on the natural spanning of Zd is recurrent for every d(= 1, 2, 3, …) and determine the asymptotic behaviour of the probability of returning to the origin in n steps (n → ∞). This is in contrast to a result of Polya [6]: Zd is recurrent for d = 1, 2 and transient for d⩾3

Carbon-doped high mobility two-dimensional hole gases on (110) faced GaAs

Carbon-doped high mobility two-dimensional hole gases grown on (110) oriented GaAs substrates have been grown with hole mobilities exceeding 10^6 cm^2/Vs in single heterojunction GaAs/AlGaAs structures. At these high mobilities, a pronounced mobility anisotropy has been observed. Rashba induced spin-splitting in these asymmetric structures has been found to be independent on the transport direction

Carbon doped symmetric GaAs/AlGaAs quantum wells with hole mobilities beyond 10^6 cm^2/Vs

Utilizing a novel carbon doping source, we prepared two-dimensional hole gases in a symmetric quantum well structure in the GaAs/AlGaAs heterosystem. Low temperature hole mobilities up to 1.2 x 10^6 cm^2/Vs at a density of 2.3 x 10^11 cm^-2 were achieved on GaAs (001) substrates. In contrast to electron systems, the hole mobility sensitively depends on variations of the quantum well width and the spacer thickness. In particular an increase of the quantum well width from an optimal value of 15 nm to 18 nm is accompanied by a 35 % reduction of the hole mobility. The quality of ultrahigh-mobility electron systems is not affected by the employed carbon doping source

Gardner optimal capacity of the diluted Blume-Emery-Griffiths neural network

The optimal capacity of a diluted Blume-Emery-Griffiths neural network is studied as a function of the pattern activity and the embedding stability using the Gardner entropy approach. Annealed dilution is considered, cutting some of the couplings referring to the ternary patterns themselves and some of the couplings related to the active patterns, both simultaneously (synchronous dilution) or independently (asynchronous dilution). Through the de Almeida-Thouless criterion it is found that the replica-symmetric solution is locally unstable as soon as there is dilution. The distribution of the couplings shows the typical gap with a width depending on the amount of dilution, but this gap persists even in cases where a particular type of coupling plays no role in the learning process.Comment: 9 pages Latex, 2 eps figure