Penrose Limit and String Theories on Various Brane Backgrounds

We investigate the Penrose limit of various brane solutions including Dp-branes, NS5-branes, fundamental strings, (p,q) fivebranes and (p,q) strings. We obtain special null geodesics with the fixed radial coordinate (critical radius), along which the Penrose limit gives string theories with constant mass. We also study string theories with time-dependent mass, which arise from the Penrose limit of the brane backgrounds. We examine equations of motion of the strings in the asymptotic flat region and around the critical radius. In particular, for (p,q) fivebranes, we find that the string equations of motion in the directions with the B field are explicitly solved by the spheroidal wave functions.Comment: 41 pages, Latex, minor correction

Do Federal Reserve policy surprises affect the risk perception in the emerging markets?

Employing an event study approach, the present authors analyse whether the Federal Reserve's policy surprises affect the risk perceptions in the emerging markets. Only weak evidence is found when the Federal Reserve follows a more expansionary policy than expected. For all other cases, the policy surprises of the Federal Reserve are ineffective. © 2006 Taylor & Francis

Sentinel Lymph Node Biopsy in Pure DCIS: Is It Necessary?

Introduction. Sentinel lymph node biopsy (SLNB) in patients with pure ductal carcinoma in situ (DCIS) has been a matter of debate due to very low rate of axillary metastases. We therefore aimed to identify factors in a single institutional series to select patients who may benefit from SLNB. Material and Methods. Patients, diagnosed with pure DCIS (n = 63) between July 2000 and March 2011, were reviewed. All the sentinel lymph nodes were examined by serial sectioning (50 μm) of the entire lymph node and H&E staining, and by cytokeratin immunostaining in suspicious cases. Results. Median age was 51 (range, 30–79). Of 63 patients, 40 cases (63.5%) with pure DCIS underwent SLN, and 2 of them had a positive SLN (5%). In both 2 cases with SLN metastases, only one sentinel lymph node was involved with tumor cells. Patients who underwent SLNB were more likely to have a tumor size >30 mm or DCIS with intermediate and high nuclear grade or a mastectomy in univariate and multivariate analyses. Conclusion. In our series, we found a slightly higher rate of SLNB positivity in patients with pure DCIS than the large series reported elsewhere. This may either be due to the meticulous examination of SLNs by serial sectioning technique or due to our patient selection criteria or both

The stochastic pump current and the non-adiabatic geometrical phase

We calculate a pump current in a classical two-state stochastic chemical kinetics by means of the non-adiabatic geometrical phase interpretation. The two-state system is attached to two particle reservoirs, and under a periodic perturbation of the kinetic rates, it gives rise to a pump current between the two-state system and the absorbing states. In order to calculate the pump current, the Floquet theory for the non-adiabatic geometrical phase is extended from a Hermitian case to a non-Hermitian case. The dependence of the pump current on the frequency of the perturbative kinetic rates is explicitly derived, and a stochastic resonance-like behavior is obtained.Comment: 11 page

Percutaneous Ventricular Restoration (PVR) Therapy Using the Parachute Device in 100 Subjects with Ischaemic Dilated Heart Failure: One-Year Primary Endpoint Results of PARACHUTE III, a European Trial

AIMS: This prospective, non-randomised, observational study conducted in Europe was designed in order to assess the long-term safety and efficacy of the Parachute device in ischaemic heart failure subjects as a result of left ventricle remodelling after anterior wall myocardial infarction. METHODS AND RESULTS: One hundred subjects with New York Heart Association Class II-IV ischaemic heart failure (HF), ejection fraction (EF) between 15% and 40%, and dilated akinetic or dyskinetic anterior-apical wall without the need to be revascularised were enrolled. The primary safety endpoint was procedural- or device-related major adverse cardiac cerebral events (MACCE). The secondary safety endpoint was the composite of mortality and morbidity. Secondary efficacy endpoints included haemodynamic measurements determined by echocardiography, LV volume indices, and assessment of functional improvement measured by a standardised six-minute walk test. Of the 100 subjects enrolled, device implantation was successful in 97 (97%) subjects. The one-year rates of the primary and secondary safety endpoints were 7% and 32.3%, respectively. The secondary endpoints, LV volume reduction (p<0.0001) and six-minute walk distance improvement (p<0.01), were achieved. CONCLUSIONS: The favourable outcomes observed in this high-risk population provide reassuring safety and efficacy data to support adoption of this technology as a therapeutic option for HF subjects.info:eu-repo/semantics/publishedVersio

Phase transitions in the boson-fermion resonance model in one dimension

We study 1D fermions with photoassociation or with a narrow Fano-Feshbach resonance described by the Boson-Fermion resonance model. Using thebosonization technique, we derive a low-energy Hamiltonian of the system. We show that at low energy, the order parameters for the Bose Condensation and fermion superfluidity become identical, while a spin gap and a gap against the formation of phase slips are formed. As a result of these gaps, charge density wave correlations decay exponentially in contrast with the phases where only bosons or only fermions are present. We find a Luther-Emery point where the phase slips and the spin excitations can be described in terms of pseudofermions. This allows us to provide closed form expressions of the density-density correlations and the spectral functions. The spectral functions of the fermions are gapped, whereas the spectral functions of the bosons remain gapless. The application of a magnetic field results in a loss of coherence between the bosons and the fermion and the disappearance of the gap. Changing the detuning has no effect on the gap until either the fermion or the boson density is reduced to zero. Finally, we discuss the formation of a Mott insulating state in a periodic potential. The relevance of our results for experiments with ultracold atomic gases subject to one-dimensional confinement is also discussed.Comment: 31 pages, 8 EPS figures, RevTeX 4, long version of cond-mat/050570

A nonlocal connection between certain linear and nonlinear ordinary differential equations/oscillators

We explore a nonlocal connection between certain linear and nonlinear ordinary differential equations (ODEs), representing physically important oscillator systems, and identify a class of integrable nonlinear ODEs of any order. We also devise a method to derive explicit general solutions of the nonlinear ODEs. Interestingly, many well known integrable models can be accommodated into our scheme and our procedure thereby provides further understanding of these models.Comment: 12 pages. J. Phys. A: Math. Gen. 39 (2006) in pres

Data mining methods for the prediction of different forms of asthma

The article examines the diagnosis of bronchial asthma, cites the classification of the disease, proves the relevance of this research, and represents the result of primary data analysis by using a powerful tool for data analysis - Rapid Miner