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We present average stochastic time-dependent Hartree–Fock (ASTDHF) as a theory for efficient handling of incoherent dynamical correlations in finite fermion systems at fully quantum-mechanical level. The basic time evolution is given by time-dependent mean-field theory. The two-body collisions beyond mean-field propagation are evaluated stochastically in an incoherent ensemble of mean-field states as was done in the previously developed STDHF. The new, and time saving, feature in ASTDHF is that it employs one common mean field throughout the whole ensemble. A detailed presentation of ASTDHF is given and extensive comparison with STDHF and other approaches to dissipation are discussed. ASTDHF is found to be a very efficient approach for well bound systems where mean-field fluctuations remain small. [ABSTRACT FROM AUTHOR]

Time-Dependent Density-Functional Theory (TDDFT) is a well-established theoretical approach to describe and understand irradiation processes in clusters and molecules. The discretization of the electronic wave functions on a spatial grid and the use of absorbing boundary conditions allows one to study electronic emission, and in particular photoelectron spectra. However, in this scheme, the unitarity of the time propagation is lost, and the set of propagated wave functions is not orthonormal anymore. This constitutes a major obstacle for extensions beyond TDDFT, e.g., to include dissipation from electronic correlations. In this work, we demonstrate that the time propagation can be done alternatively in an orthonormal basis, the so-called set of “natural orbitals”, with results very similar to the usual time propagation, even for the more involved photo-emission spectrum. This technique will serve as a basis for including dynamical correlations. [ABSTRACT FROM AUTHOR]

We apply in a schematic model a theory beyond mean-field, namely Stochastic Time-Dependent Hartree–Fock (STDHF), which includes dynamical electron–electron collisions on top of an incoherent ensemble of mean-field states by occasional 2-particle–2-hole ( 2 p 2 h ) jumps. The model considered here is inspired by a Lipkin–Meshkov–Glick model of Ω particles distributed into two bands of energy and coupled by a two-body interaction. Such a model can be exactly solved (numerically though) for small Ω . It therefore allows a direct comparison of STDHF and the exact propagation. The systematic impact of the model parameters as the density of states, the excitation energy and the bandwidth is presented and discussed. The time evolution of the STDHF compares fairly well with the exact entropy, as soon as the excitation energy is sufficiently large to allow 2 p 2 h transitions. Limitations concerning low energy excitations and memory effects are also discussed. [ABSTRACT FROM AUTHOR]

Background: Treatment of localised renal cell carcinoma consists of partial or radical nephrectomy. A substantial proportion of patients are at risk for recurrence because no effective adjuvant therapy exists. We investigated the use of an autologous, tumour-derived heat-shock protein (glycoprotein 96)-peptide complex (HSPPC-96; vitespen) as adjuvant treatment in patients at high risk of recurrence after resection of locally advanced renal cell carcinoma.Methods: In this open-label trial, patients were randomly assigned to receive either vitespen (n=409) or observation alone (n=409) after nephrectomy. Randomisation was done in a one to one ratio by a computer-generated pseudo-random number generator, with a block size of four, and was stratified by performance score, lymph node status, and nuclear grade. Vitespen was given intradermally once a week for 4 weeks, then every 2 weeks until vaccine depletion. The primary endpoint was recurrence-free survival. The final analysis of recurrence-free survival was planned to take place after 214 or more events of disease recurrence or deaths before recurrence had occurred. Analysis was by intention to treat (ITT). This study is registered with ClinicalTrials.gov, number NCT00033904.Findings: 48 patients in the vitespen group and 42 in the observation group were excluded from the ITT population because they did not meet post-surgery inclusion criteria; the ITT population thus consisted of 361 patients in the vitespen group and 367 in the observation group. Final analysis of recurrence-free survival was triggered in November, 2005. Re-review of all patients in the ITT population by the clinical events committee identified 149 actual recurrences (73 in the vitespen group and 76 in the observation group), nine deaths before recurrence (two in the vitespen group and seven in the observation group), and 124 patients with baseline metastatic or residual disease (61 in the vitespen group and 63 in the observation group). Thus, after a median follow-up of 1.9 years (IQR 0.9-2.5) in the ITT population, recurrence events were reported in 136 (37.7%) patients in the vitespen group and 146 (39.8%) in the observation group (hazard ratio 0.923, 95% CI 0.729-1.169; p=0.506). After continued follow-up until March, 2007, there had been 70 deaths in the vitespen group and 72 in the observation group (p=0.896); however, overall survival data were not mature, and patients continue to be followed up for survival. In predefined exploratory analyses by AJCC stage, recurrence events in patients with stage I or II disease were reported in 19 (15.2%) patients in the vitespen group and 31 (27.0%) in the observation group (hazard ratio 0.576, 95% CI 0.324-1.023; p=0.056). The most commonly reported adverse events in the vitespen group were injection-site erythema (n=158) and injection-site induration (n=153). One serious adverse event-autoimmune thyroiditis of grade 2 severity-was reported in the vitespen group; no treatment-related grade 3 or 4 adverse events were reported.Interpretation: No difference in recurrence-free survival was seen between patients given vitespen and those who received no treatment after nephrectomy for renal cell carcinoma. A possible improvement in recurrence-free survival in patients with early stage disease who received vitespen will require further validation. [ABSTRACT FROM AUTHOR]