Spin-wave amplification and lasing driven by inhomogeneous spin-transfer torques

We show that an inhomogeneity in the spin-transfer torques in a metallic ferromagnet under suitable conditions strongly amplifies incoming spin waves. Moreover, at nonzero temperatures the incoming thermally occupied spin waves will be amplified such that the region with inhomogeneous spin-transfer torques emits spin waves spontaneously, thus constituting a spin-wave laser. We determine the spin-wave scattering amplitudes for a simplified model and setup, and show under which conditions the amplification and lasing occurs. Our results are interpreted in terms of a so-called black-hole laser, and could facilitate the field of magnonics, which aims to utilize spin waves in logic and data-processing devices.</p

The embedding method beyond the single-channel case: Two-mode and Hubbard chains

We investigate the relationship between persistent currents in multi-channel rings containing an embedded scatterer and the conductance through the same scatterer attached to leads. The case of two uncoupled channels corresponds to a Hubbard chain, for which the one-dimensional embedding method is readily generalized. Various tests are carried out to validate this new procedure, and the conductance of short one-dimensional Hubbard chains attached to perfect leads is computed for different system sizes and interaction strengths. In the case of two coupled channels the conductance can be obtained from a statistical analysis of the persistent current or by reducing the multi-channel scattering problem to several single-channel setups.Comment: 14 pages, 13 figures, submitted for publicatio

Gravitational quasinormal radiation of higher-dimensional black holes

We find the gravitational resonance (quasinormal) modes of the higher dimensional Schwarzschild and Reissner-Nordstrem black holes. The effect on the quasinormal behavior due to the presence of the $\lambda$ term is investigated. The QN spectrum is totally different for different signs of $\lambda$. In more than four dimensions there excited three types of gravitational modes: scalar, vector, and tensor. They produce three different quasinormal spectra, thus the isospectrality between scalar and vector perturbations, which takes place for D=4 Schwarzschild and Schwarzschild-de-Sitter black holes, is broken in higher dimensions. That is the scalar-type gravitational perturbations, connected with deformations of the black hole horizon, which damp most slowly and therefore dominate during late time of the black hole ringing.Comment: 13 pages, 2 figures, several references are adde

Misleading signatures of quantum chaos

The main signature of chaos in a quantum system is provided by spectral statistical analysis of the nearest neighbor spacing distribution and the spectral rigidity given by $\Delta_3(L)$. It is shown that some standard unfolding procedures, like local unfolding and Gaussian broadening, lead to a spurious increase of the spectral rigidity that spoils the $\Delta_3(L)$ relationship with the regular or chaotic motion of the system. This effect can also be misinterpreted as Berry's saturation.Comment: 4 pages, 5 figures, submitted to Physical Review

Effect of various dietary regimens on oral challenge with Mycobacterium avium subsp. paratuberculosis in a rabbit model

Rabbits are susceptible to infection by Mycobacterium avium subspecies paratuberculosis (MAP) in both wildlife and experimental conditions. Under the hypotheses that nutrient balance might influence the establishment of infection, we designed an experiment where MAP intestinal colonization was assessed under three dietary regimens: high fiber, high protein, and regular diet in New Zealand white rabbits submitted to oral challenge with MAP.Lowest weight gain (F=5.17, p=0.024), higher tissue culture positivity rates (X2=7.43, p=0.024) and especially extended MAP-compatible lesions (F=5.78, p=0.017) were detected in the regular diet.Taken altogether, results indicate that paratuberculosis infection was achieved affecting mostly regular diet animals and showing that dietary changes may modulate the course of the infection

PCUMex survey: Controversies in the management of prostate cancer among Mexican urologists

AbstractBackgroundProstate cancer is the first cause of mortality related to malignancy in Mexican men. Common clinical practice has to be evaluated in order to gain a picture of reality apart from the guidelines.AimTo analyze clinical practice among urologists in Mexico in relation to prostate cancer management and to compare the results with current recommendations and guidelines.MethodsWe collected the data from 600 urologists, members of the Sociedad Mexicana de Urología, who were invited by email to answer a survey on their usual decisions when managing controversial aspects of prostate cancer patients.ResultsQuinolones were the most common antibiotic used as prophylaxis in prostate biopsy (75.51%); 10–12 cores were taken in more than 65% of prostate biopsies; and 18.27% of the participants performed limited pelvic lymphadenectomy. Treatment results showed that 10.75% of the urologists surveyed preferred radical prostatectomy as monotherapy in high-risk patients with extraprostatic extension and 60.47% used complete androgen deprivation in metastatic prostate cancer.ConclusionsThere are many areas of opportunity for improvement in our current clinical practice for the management of patients with prostate cancer

Cosmological parameter estimation using Very Small Array data out to ℓ= 1500

We estimate cosmological parameters using data obtained by the Very Small Array (VSA) in its extended configuration, in conjunction with a variety of other cosmic microwave background (CMB) data and external priors. Within the flat Λ cold dark matter (ΛCDM) model, we find that the inclusion of high-resolution data from the VSA modifies the limits on the cosmological parameters as compared to those suggested by the Wilkinson Microwave Anisotropy Probe (WMAP) alone, while still remaining compatible with their estimates. We find that Ωbh2= 0.0234+0.0012−0.0014, Ωdmh2= 0.111+0.014−0.016, h= 0.73+0.09−0.05, nS= 0.97+0.06−0.03, 1010AS= 23+7−3 and τ= 0.14+0.14−0.07 for WMAP and VSA when no external prior is included. On extending the model to include a running spectral index of density fluctuations, we find that the inclusion of VSA data leads to a negative running at a level of more than 95 per cent confidence ( nrun=−0.069 ± 0.032 ), something that is not significantly changed by the inclusion of a stringent prior on the Hubble constant. Inclusion of prior information from the 2dF galaxy redshift survey reduces the significance of the result by constraining the value of Ωm. We discuss the veracity of this result in the context of various systematic effects and also a broken spectral index model. We also constrain the fraction of neutrinos and find that fν < 0.087 at 95 per cent confidence, which corresponds to mν < 0.32 eV when all neutrino masses are equal. Finally, we consider the global best fit within a general cosmological model with 12 parameters and find consistency with other analyses available in the literature. The evidence for nrun < 0 is only marginal within this model

Resultados oncológicos en enfermedad N1 posterior a la prostatectomía radical

ResumenAntecedentesLa prostatectomía radical+linfadenectomía pélvica puede mejorar la supervivencia libre de progresión y supervivencia cáncer-específica en la enfermedad ganglionar.ObjetivoAnalizar las características de los pacientes con enfermedad ganglionar en el análisis histopatológico de la prostatectomía radical.Material y métodosEstudio retrospectivo de pacientes sometidos a prostatectomía radical con enfermedad ganglionar metastásica de 1988 a 2015.ResultadosSe incluyeron 25 pacientes, de 66.5 años (DE±6.5); antígeno prostático específico medio de 20.17ng/dL (RIC: 18); con una mediana de seguimiento en 63 meses (RIC: 86). Clasificación de riesgo por D’Amico, 15 (60%) pacientes de alto, 8 (32%) intermedio y 2 (8%) de riesgo bajo. Se encontraron márgenes positivos en 15 casos (60%); estadio tumoral T2 en 4 (16%), T3A en 3 (12%), T3B en 17 (68%) y T4 en 1 (4%); cantidad de ganglios positivos, uno en 14 (56%), 2 en 3 (12%) y más de 2 en 8 (32%) casos. Recibieron radioterapia 3 pacientes (16%) y bloqueo hormonal 24 (96%). La supervivencia libre de progresión fue de 105 meses y la supervivencia cáncer-específica fue del 86 y 45% a 5 y 10 años respectivamente. El HR para progresión bioquímica fue significativo en márgenes positivos (HR: 9.5, IC95%: 0.99-91.5, p=0.50) y ≥2 ganglios positivos (HR: 8.5, IC95%: 1.1-61.9, p=0.34). La afectación≥2 ganglios predijo progresión con una OR de 7.2 (IC95% 1.06-48.6, p=0.043).ConclusionesLa supervivencia media a 5 años es superior al 80%. El número de ganglios positivos podría ser un factor predictor de progresión bioquímica.AbstractBackgroundRadical prostatectomy+pelvic lymph node dissection can improve progression-free survival and cancer-specific survival in lymph node disease.AimTo analyze the characteristics of patients with lymph node disease in the histopathologic findings of the radical prostatectomy and lymph node dissection.Material and methodsA retrospective study was carried out on patients that underwent radical prostatectomy with metastatic lymph node disease within the time frame of 1988 to 2015.ResultsThe study included 25 patients with a mean 66.5 years of age (SD±6.5), a mean prostate-specific antigen of 20.17ng/dl (IQR: 18), and a median follow-up period of 63 months (IQR: 86). According to the D’Amico classification, 15 (60%) patients were high-risk, 8 (32%) were intermediate-risk, and 2 (8%) were low-risk. Positive margins were found in 15 cases (60%); 4 (16%) patients had T2 tumor stage, 3 (12%) had T3A, 17 (68%) had T3B, and one patient (4%) had T4. Fourteen (56%) patients had one positive lymph node, 3 (12%) patients had 2 positive lymph nodes, and 8 (32%) patients had more than 2 positive lymph nodes. Three (16%) patients received radiotherapy and 24 (96%) underwent hormone blockade. Progression-free survival was 105 months and cancer-specific survival was 86% at 5 years and 45% at ten years. The HR for biochemical progression was significant in positive margins (HR: 9.5, 95% CI: 0.99-91.5, P=.50) and when there were≥2 positive lymph nodes (HR: 8.5, 95% CI: 1.1-61.9, P=0.34). Involvement of≥2 lymph nodes predicted progression with an odds ratio of 7.2 (95% CI: 1.06-48.6, P=.043).ConclusionsThe average 5-year survival was above 80%. The number of positive lymph nodes could be a predictive factor for biochemical progression

Field propagation in de Sitter black holes

We present an exhaustive analysis of scalar, electromagnetic and gravitational perturbations in the background of Schwarzchild-de Sitter and Reissner-Nordstrom-de Sitter spacetimes. The field propagation is considered by means of a semi-analytical (WKB) approach and two numerical schemes: the characteristic and general initial value integrations. The results are compared near the extreme cosmological constant regime, where analytical results are presented. A unifying picture is established for the dynamics of different spin fields.Comment: 15 pages, 16 figures, published versio

High prevalence and diversity of extended-spectrum β-lactamase and emergence of OXA-48 producing Enterobacterales in wildlife in Catalonia

The contract of LMG was supported by the Instituto Nacional de Investigaci?n y Tecnolog?a Agraria y Alimentaria (INIA) and the European Social Fund. AV was supported by a PIF grant from the Universitat Aut?noma de Barcelona. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Our grateful thanks to the Torreferrussa WRC staff. A.C. was student of the Master?s Degree in Zoonosis and One Health (UAB). The authors are also grateful to the Centres de Recerca de Catalunya (CERCA) Programme.Most of the studies focused on antimicrobial resistance (AMR) performed in wildlife describe Escherichia coli as the principal indicator of the selective pressure. In the present study, several species of Enterobacterales with a large panel of cephalosporin resistant (CR) genes have been isolated from wildlife in Catalonia. A total of 307 wild animals were examined to determine the prevalence of CR enterobacteria, AMR phenotypes and the presence of common carbapenem and CR genes. The overall prevalence of CR-phenotype was 13% (40/ 307): 17.3% in wild mammals (18/104) and 11.5% in wild birds (22/191) (p<0.01). Hedgehogs showed the highest prevalence (13.5% of 104) of the mammal specimens, and raptors the highest in bird specimen (7.3% of 191). Although CR E. coli was the most frequently isolated (45%), other CR- Enterobacterales like Klebsiella pneumoniae (20%), Citrobacter freundii (15%), Enterobacter cloacae (5%), Proteus mirabilis (5%), Providencia spp (5%) and Serratia marcescens (2.5%) were also isolated. A high diversity of CR genes was identified among the isolates, with 50% yielding blaCMY-2, 23% blaSHV-12, 20% blaCMY-1 and 18% blaCTX-M-15. Additionally, resistance to carbapenems associated to OXA-48 gene was found. Most of the CR isolates, principally K. pneumoniae and C. freundii, were multiresistant with co-resistance to fluoroquinolones, tetracycline, sulphonamides and aminoglycosides. This study reports high prevalence of Enterobacterales harbouring a variety of CR genes and OXA-48 mediated-carbapenem resistance, all of them frequently associated to nosocomial human infections, for the first time in wild mammals and wild birds. Implementation of control measures to reduce the impact of anthropogenic pressure in the environment is urgently needed