Rational functions associated with double infinite sequences of complex numbers

AbstractLet {μk}−∞+∞ be a given double infinite sequence of complex numbers. By defining a linear functional on the space of the Laurent polynomials, certain rational functions are first constructed and some algebraic properties studied.The hermitian case, i.e. μ−k = μk, k ∈ Z is separately considered and it is shown how the theory of polynomials orthogonal on the unit circle can be used in order to prove geometric convergence for sequences such as these rational functions

A note on hermite-fejér interpolation for the unit circle

AbstractIn this note, an extension to the unit circle of the classical Hermite-Fejér Theorem is given

Two-point Padé-type approximation to the Cauchy transform of certain strong distributions

AbstractIn this paper we are mainly concerned with the Cauchy transform of certain strong distributions satisfying a type of symmetric property introduced by A.S. Ranga. Algebraic properties of the corresponding two-point Padé-type approximants are given along with results about convergence for sequences of such approximant

High-dimensional decoy-state quantum key distribution over 0.3 km of multicore telecommunication optical fibers

Multiplexing is a strategy to augment the transmission capacity of a communication system. It consists of combining multiple signals over the same data channel and it has been very successful in classical communications. However, the use of enhanced channels has only reached limited practicality in quantum communications (QC) as it requires the complex manipulation of quantum systems of higher dimensions. Considerable effort is being made towards QC using high-dimensional quantum systems encoded into the transverse momentum of single photons but, so far, no approach has been proven to be fully compatible with the existing telecommunication infrastructure. Here, we overcome such a technological challenge and demonstrate a stable and secure high-dimensional decoy-state quantum key distribution session over a 0.3 km long multicore optical fiber. The high-dimensional quantum states are defined in terms of the multiple core modes available for the photon transmission over the fiber, and the decoy-state analysis demonstrates that our technique enables a positive secret key generation rate up to 25 km of fiber propagation. Finally, we show how our results build up towards a high-dimensional quantum network composed of free-space and fiber based linksComment: Please see the complementary work arXiv:1610.01812 (2016

Tratamiento quirúrgico en las cifosis congénitas: Revisión de 14 pacientes

Los autores efectúan una revisión de 14 pacientes con cifosis congénita, intervenidos entre los años 1979-1989, con un seguimiento medio de 7 años. La edad media preoperatoria fue de 11 años (todos ellos mayores de 5 años), con una cifosis media de 7 9 . En 6 casos se realizó una artrodesis posterior y en 8 una anterior combinada con una fusión posterior. Inicialmente obtuvieron una corrección media de la curva de 18° con la artrodesis posterior y 20° con la artrodesis combinada. La pérdida postoperatoria final fue de 10° y 8° respectivamente. En un caso, se produjo una pseudoartrosis por fusión corta. Como complicaciones postoperatorias en 5 pacientes, una radiculopatía, una infección superficial y cuatro protusiones de material que requirieron su extracción. Los autores analizan los factores que han podido influir en los resultados obtenidos, comparándolos posteriormente con los conseguidos por otros centros hospitalarios importantes.Fourteen patients with congenital kyphosis treated surgically between 1979- 1989 were reviewed. All had a follow-up of 2 years or more, with an average follow-up of 7 years. The average age at surgery was 11 and the average kyphosis was 79°. Six cases had posterior fusion only and eigth had combined anterior and posterior fusion. The results showed an average correction of the curve at surgery of 18° with posterior arthrodesis and 20° with combined arthrodesis. There was thus an average loss of 10° and 8° respectively from the time of surgery in both types of treatment. Pseudoarthrosis by short fusion ocurred in one case. Other complications after surgery were 1 radiculopathy, one wound infection and four rod protusion (six patients). The factors that have influence in this results were analysed. A comparison from the results of treatment at other medical centers was also carried out

A local characterisation for static charged black holes

We obtain a purely local characterisation that singles out the Majumdar-Papapetrou class, the near-horizon Bertotti-Robinson geometry and the Reissner-Nordstr\"om exterior solution, together with its plane and hyperbolic counterparts, among the static electrovacuum spacetimes. These five classes are found to form the whole set of static Einstein-Maxwell fields without sources and conformally flat space of orbits, this is, the conformastat electrovacuum spacetimes. The main part of the proof consists in showing that a functional relationship between the gravitational and electromagnetic potentials must always exist. The classification procedure provides also an improved characterisation of Majumdar-Papapetrou, by only requiring a conformally flat space of orbits with a vanishing Ricci scalar of the usual conveniently rescaled 3-metric. A simple global consideration allows us to state that the asymptotically flat subset of the Majumdar-Papapetrou class and the Reissner-Nordstr\"om exterior solution are the only asymptotically flat conformastat electrovacuum spacetimes.Comment: LaTeX; 31 pages. Uses iopart style file

Pattern speed of main spiral arms in NGC 2997: Estimate based on very young stellar complexes

Deep JHK-Brg photometry of the southern arm of the grand-design spiral galaxy NGC 2997 was obtained by ISAAC/VLT. All sources in the field brighter than K=19 mag were located. Color-color diagrams were used to identify young stellar complexes among the extended sources. Ages can be estimated for the youngest complexes and correlated with azimuthal distances from the spiral arms defined by the K-band intensity variation. The extended sources with Mk <-12 mag display a diffuse appearance and are more concentrated inside the arm region than fainter ones, which are compact and uniformly distributed in the disk. The NIR colors of the bright diffuse objects are consistent with them being young starforming complexes with ages <10 Myr and reddened by up to 8 mag of visual extinction. They show a color gradient as a function of their azimuthal distance from the spiral arms. Interpreting this gradient as an age variation, the pattern speed Op = 16 km/s/kpc of the main spiral was derived assuming circular motion. The alignment and color gradient of the bright, diffuse complexes strongly support a density wave scenario for NGC 2997. Only the brightest complexes with Mk <-12 mag show a well aligned structure along the arm, suggesting that a strong compression in the gas due to the spiral potential is required to form these most massive aggregates, while smaller starforming regions are formed more randomly in the disk. The sharp transition between the two groups at Mk = -12 mag may be associated with expulsion of gas when the first supernovae explode in the complex.Comment: 4 pages, 5 figures. Accepted for publication as A&A Lette

Intratumoral injection of dendritic cells transduced by an SV40-based vector expressing interleukin-15 induces curative immunity mediated by CD8+ T lymphocytes and NK cells

Cancer immunotherapy has been extensively attempted by gene transfer of cytokines with viral vectors. In this work, we compared the therapeutic effects of interleukin 12 and 15 (IL-12 and IL-15) genes transferred to tumor cells or to dendritic cells (DCs), which were subsequently injected into established tumors. For this purpose, we used viral vectors based on simian virus 40 (rSV40). Importantly, we observed that nonmatured DCs infected with rSV40 vectors remained phenotypically immature. Infection of CT-26 tumor cells with rSV40 expressing IL-12 (rSVIL-12) or IL-15 (rSVIL-15) failed to inhibit tumor development. In contrast, the intratumoral administration of syngeneic DCs transduced with rSVIL-12 or rSVIL-15 was associated with a strong antitumor response; up to 40% tumor remissions were achieved with DCs transduced by rSVIL-12 and 73% with DCs expressing IL-15. This antitumor effect correlated with the in vivo priming of tumor-specific CD8+ T lymphocytes. Depletion studies showed that rSVIL-15-mediated antitumor efficacy was mediated mainly by CD8+ T lymphocytes and NK cells. We conclude that (i) SV40-derived vectors are an advantageous alternative to transduce genes into DCs and (ii) DCs transferred with IL-15 have an enhanced capability to induce curative antitumor immunity when injected into malignant lesions

Clinical and epidemiological characterization of a lymphogranuloma venereum outbreak in Madrid, Spain: co-circulation of two variants

AbstractThe lymphogranuloma venereum (LGV) outbreak described in the Netherlands in 2003, increased the interest in the genotyping of Chlamydia trachomatis. Although international surveillance programmes were implemented, these studies slowly decreased in the following years. Now data have revealed a new accumulation of LGV cases in those European countries with extended surveillance programmes. Between March 2009 and November 2011, a study was carried out to detect LGV cases in Madrid. The study was based on screening of C. trachomatis using commercial kits, followed by real-time pmpH-PCR discriminating LGV strains, and finally ompA gene was sequenced for phylogenetic reconstruction. Ninety-four LGV infections were identified. The number of cases increased from 10 to 30 and then to 54 during 2009–2011. Incidence of LGV was strongly associated with men who have sex with men; but in 2011, LGV cases were described in women and heterosexual men. Sixty-nine patients were also human immunodeficiency virus (HIV) positive, with detectable viral loads at the moment of LGV diagnosis, suggesting a high-risk of co-transmission. In fact, in four patients the diagnosis of HIV was simultaneous with LGV infection. The conventional treatment with doxycycline was prescribed in 75 patients, although in three patients the treatment failed. The sequencing of the ompA gene permitted identification of two independent transmission nodes. One constituted by 25 sequences identical to the L2b variant, and a second node including 37 sequences identical to L2. This epidemiological situation characterized by the co-circulation of two LGV variants has not been previously described, reinforcing the need for screening and genotyping of LGV strains