Nonequilibrium Spin Dynamics in the Ferromagnetic Kondo Model

Motivated by recent experiments on molecular quantum dots we investigate the relaxation of pure spin states when coupled to metallic leads. Under suitable conditions these systems are well described by a ferromagnetic Kondo model. Using two recently developed theoretical approaches, the time-dependent numerical renormalization group and an extended ow equation method, we calculate the real-time evolution of a Kondo spin into its partially screened steady state. We obtain exact analytical results which agree well with numerical implementations of both methods. Analytical expressions for the steady state magnetization and the dependence of the long-time relaxation on microscopic parameters are established. We find the long-time relaxation process to be much faster in the regime of anisotropic Kondo couplings. The steady state magnetization is found to deviate significantly from its thermal equilibrium value.Comment: 4 pages, 3 figures, final version as accepted by Physical Review Letter

Microbial colonization and ureteral stent-associated storage lower urinary tract symptoms: the forgotten piece of the puzzle?

Purpose: Ureteral stents are frequently associated with side effects. Most patients suffer from storage lower urinary tract symptoms (LUTS). Storage LUTS are commonly attributed to the irritation of the trigone, smooth muscle spasm or a combination of factors. The relationship between microbial ureteral stent colonization (MUSC) and de novo or worsening storage LUTS has not been investigated yet. Methods: Five hundred ninety-one polyurethane ureteral stents from 275 male and 153 female patients were prospectively evaluated. The removed stents were sonicated to dislodge adherent microorganisms. Urine flow cytometry was performed to detect pyuria. A standardized urinary symptom questionnaire was given to all patients. Results: Thirty-five per cent of male and 28% of female cases showed de novo or worsened storage LUTS. MUSC was more common in patients with storage LUTS compared to patients without storage LUTS (men: 26 vs. 13%, respectively, P<0.05; women: 63 vs. 48%, respectively, P=0.13). Pyuria was significantly more common in patients with storage LUTS compared to patients without storage LUTS (men: 55 vs. 40%, respectively, P<0.05; women: 70 vs. 45%, respectively, P<0.05). No significant correlation was observed between the detected genera of microorganisms and storage LUTS. Conclusions: Our data show a significant association between MUSC- and stent-related de novo experienced or worsened storage LUTS in men. The incidence of MUSC is most common in both female and male patients with storage LUTS and accompanying pyuria. In these patients, a combination of antibiotics and anti-inflammatory drugs may be regarded as treatment optio

Microsatellite diversity of the Nordic type of goats in relation to breed conservation: how relevant is pure ancestry?

In the last decades, several endangered breeds of livestock species have been re-established effectively. However, the successful revival of the Dutch and Danish Landrace goats involved crossing with exotic breeds and the ancestry of the current populations is therefore not clear. We have generated genotypes for 27 FAO-recommended microsatellites of these landraces and three phenotypically similar Nordic-type landraces and compared these breeds with central European, Mediterranean and south-west Asian goats. We found decreasing levels of genetic diversity with increasing distance from the south-west Asian domestication site with a south-east-to-north-west cline that is clearly steeper than the Mediterranean east-to-west cline. In terms of genetic diversity, the Dutch Landrace comes next to the isolated Icelandic breed, which has an extremely low diversity. The Norwegian coastal goat and the Finnish and Icelandic landraces are clearly related. It appears that by a combination of mixed origin and a population bottleneck, the Dutch and Danish Land-races are separated from the other breeds. However, the current Dutch and Danish populations with the multicoloured and long-horned appearance effectively substitute for the original breed, illustrating that for conservation of cultural heritage, the phenotype of a breed is more relevant than pure ancestry and the genetic diversity of the original breed. More in general, we propose that for conservation, the retention of genetic diversity of an original breed and of the visual phenotype by which the breed is recognized and defined needs to be considered separately

Measurement of charged particle spectra in deep-inelastic ep scattering at HERA

Charged particle production in deep-inelastic ep scattering is measured with the H1 detector at HERA. The kinematic range of the analysis covers low photon virtualities, 5 LT Q(2) LT 100 GeV2, and small values of Bjorken-x, 10(-4) LT x LT 10(-2). The analysis is performed in the hadronic centre-of-mass system. The charged particle densities are measured as a function of pseudorapidity (n(*)) and transverse momentum (p(T)(*)) in the range 0 LT n(*) LT 5 and 0 LT p(T)(*) LT 10 GeV in bins of x and Q(2). The data are compared to predictions from different Monte Carlo generators implementing various options for hadronisation and parton evolutions