The association of acylcarnitines and amino acids with age in Dutch and South-Asian Surinamese living in Amsterdam.

Type 2 diabetes and cardiovascular disease occur more frequently, and at a younger age in South-Asians than Europeans. This may be related to differences in regulation of the fatty acid metabolism during aging. We compared age-related acylcarnitine and amino acid concentrations. We measured types of acylcarnitine and amino acid concentrations in plasma (by tandem-MS) in a random subsample of 350 Dutch and 350 South-Asian Surinamese origin participants of the HELIUS study (Amsterdam, The Netherlands). We derived principal components (PCs) from the metabolites. Linear regression was used to assess differences in PCs and individual metabolite concentrations, and their age-trends between the groups by sex. We adjusted for BMI and intake of fat and total energy. Mean age was 44.8 (SD 13.3) years. Many metabolite concentrations were higher among South-Asian Surinamese participants compared to Dutch participants; amino acids in women, and both acylcarnitines and amino acids in men. Metabolite levels increased similarly with age in both ethnic groups. Results remained similar after adjustment. Ethnic differences in metabolite concentrations suggest that fatty acid and amino acid metabolism are more dysregulated among South-Asian Surinamese compared to Dutch from a young age. During adulthood metabolites increase similarly in both ethnic groups

String Theory on Dp-plane waves

We study the spectrum of solvable string models on plane waves descending from non-conformal Dp-brane geometries. We mainly focus on S-dual F1/D1-waves in type IIB and type I/heterotic 10D superstrings. We derive the Kaluza-Klein spectrum of N=1,2 10D supergravities on D1/F1-waves. We compute helicity supertraces counting multiplicities and R-charges of string excitations in the plane wave geometry. The results are compared against the expectations coming from gauge/supergravity descriptions. In the type I case, the Klein, Annulus and Moebius one-loop amplitudes are computed for ten-dimensional D1-waves. We test the consistency of the open string descendant by showing that after modular transformations to the closed string channel, the three amplitudes combine themselves to reconstruct a complete square (|B>+|C>)^2. Tadpole conditions are also discussed.Comment: 22 pages, Minor corrections, References adde

An example of localized D-branes solution on PP-wave backgrounds

In this note we provide an explicit example of type IIB supersymmetric D3-branes solution on a pp-wave like background, consisting in the product of an eight-dimensional pp-wave times a two-dimensional flat space. An interesting property of our solution is the fully localization of the D3-branes (i.e. the solution depends on all the transverse coordinates). Then we show the generalization to other Dp-branes and to the D1/D5 system.Comment: 14 pages, 1 table; v2. references adde

Quenching of Weak Interactions in Nucleon Matter

We have calculated the one-body Fermi and Gamow-Teller charge-current, and vector and axial-vector neutral-current nuclear matrix elements in nucleon matter at densities of 0.08, 0.16 and 0.24 fm$^{-3}$ and proton fractions ranging from 0.2 to 0.5. The correlated states for nucleon matter are obtained by operating on Fermi-gas states by a symmetrized product of pair correlation operators determined from variational calculations with the Argonne v18 and Urbana IX two- and three-nucleon interactions. The squares of the charge current matrix elements are found to be quenched by 20 to 25 % by the short-range correlations in nucleon matter. Most of the quenching is due to spin-isospin correlations induced by the pion exchange interactions which change the isospins and spins of the nucleons. A large part of it can be related to the probability for a spin up proton quasi-particle to be a bare spin up/down proton/neutron. We also calculate the matrix elements of the nuclear Hamiltonian in the same correlated basis. These provide relatively mild effective interactions which give the variational energies in the Hartree-Fock approximation. The calculated two-nucleon effective interaction describes the spin-isospin susceptibilities of nuclear and neutron matter fairly accurately. However $\geq$ 3-body terms are necessary to reproduce the compressibility. All presented results use the simple 2-body cluster approximation to calculate the correlated basis matrix elements.Comment: submitted to PR

Hole-doping dependence of percolative phase separation in Pr_(0.5-delta)Ca_(0.2+delta)Sr_(0.3)MnO_(3) around half doping

We address the problem of the percolative phase separation in polycrystalline samples of Pr$_{0.5-\delta}$Ca$_{0.2+\delta}$Sr$_{0.3}$MnO$_3$ for $-0.04\leq \delta \leq 0.04$ (hole doping $n$ between 0.46 and 0.54). We perform measurements of X-ray diffraction, dc magnetization, ESR, and electrical resistivity. These samples show at $T_C$ a paramagnetic (PM) to ferromagnetic (FM) transition, however, we found that for $n>0.50$ there is a coexistence of both of these phases below $T_C$. On lowering $T$ below the charge-ordering (CO) temperature $T_{CO}$ all the samples exhibit a coexistence between the FM metallic and CO (antiferromagnetic) phases. In the whole $T$ range the FM phase fraction ($X$) decreases with increasing $n$. Furthermore, we show that only for $n\leq 0.50$ the metallic fraction is above the critical percolation threshold $X_C\simeq 15.5$. As a consequence, these samples show very different magnetoresistance properties. In addition, for $n\leq 0.50$ we observe a percolative metal-insulator transition at $T_{MI}$, and for $T_{MI}<T<T_{CO}$ the insulating-like behavior generated by the enlargement of $X$ with increasing $T$ is well described by the percolation law $\rho ^{-1}=\sigma \sim (X-X_C)^t$, where $t$ is a critical exponent. On the basis of the values obtained for this exponent we discuss different possible percolation mechanisms, and suggest that a more deep understanding of geometric and dimensionality effects is needed in phase separated manganites. We present a complete $T$ vs $n$ phase diagram showing the magnetic and electric properties of the studied compound around half doping.Comment: 9 text pages + 12 figures, submitted to Phys. Rev.

Complicaciones de la colocación de malla sintética vaginal para la incontinencia urinaria de esfuerzo

ResumenAntecedentesLas mallas para la incontinencia urinaria (IU) se han utilizado a pesar de la falta de evidencia de nivel i en la literatura para evaluar su seguridad y eficacia a largo plazo. Las complicaciones relacionadas con la malla provocaron una advertencia emitida por la FDA en 2008 y dejaron de ser consideradas eventos raros. Las complicaciones más comunes son la retención aguda de orina, sangrado, recurrencia o persistencia de la IU, erosión de uretra e infección de la malla.ObjetivoConocer cuáles son las complicaciones derivadas del tratamiento quirúrgico de la IU femenina con la colocación de mallas suburetrales.Material y métodoSe analizaron los pacientes con diagnóstico de IU operadas con cirugía antiincontinencia y colocación de malla vaginal del año 2007 al 2014. Se analizó las complicaciones derivadas de la colocación de malla y la recuperación de continencia.ResultadosA 58 pacientes se les colocó sling (cabestrillo) con malla sintética; edad promedio de 56 años. El 51% de las pacientes tenían IU de esfuerzo y el 49% IU mixta. Las complicaciones tempranas fueron: 4 pacientes con retención aguda de orina. Las complicaciones tardías: dolor uretral o vaginal (12.2%), dispareunia (20%) y extrusión de malla (10%) manejado con retiro de la misma, 2 de ellas requiriendo 2 procedimientos quirúrgicos. El 12% presentaron urgencia de novo, el 90.2% evolucionaron sin incontinencia, el 9.7% con IU postoperatoria y 2 pacientes sin mejoría.DiscusiónNuestra serie, aunque pequeña, muestra una baja tasa de complicaciones a largo plazo relacionadas con la malla en comparación con la mayoría de las series que muestran una tasa de reoperación de hasta>70% y con múltiples casos de retiro de malla, por lo que en nuestra experiencia los slings suburetrales continúan siendo una opción adecuada en el manejo de la IU.ConclusionesLos slings suburetrales son una opción segura y efectiva en el manejo de la IU.AbstractBackgroundSurgical mesh has been used for treating urinary incontinence (UI) despite the lack of level i evidence in the literature evaluating its long-term safety and efficacy. Mesh-related complications were responsible for a warning issued by the FDA in 2008 and they stopped being considered rare events. The most common complications are acute urinary retention, bleeding, recurrence or persistence of UI, erosion of the urethra, and mesh infection.AimsTo determine the complications derived from surgical UI treatment with the placement of suburethral mesh in women.Material and methodPatients diagnosed with UI that underwent anti-incontinence surgery with the placement of vaginal mesh within the time frame of 2007 and 2014 were analyzed. Mesh placement complications and the recovery of continence were evaluated.ResultsA synthetic mesh sling was placed in 58 patients with a mean age of 56 years. A total of 51% of the patients had stress urinary incontinence and 49% had mixed urinary incontinence. Early complications were: 4 patients with acute urine retention. Late complications were: urethral or vaginal pain (12.2%), dyspareunia (20%), and mesh extrusion (10%) that was managed through mesh removal; 2 of those patients required surgical procedures. Twelve percent of the patients presented with de novo urgency, 90.2% progressed with no incontinence, 9.7% presented with postoperative UI, and 2 patients had no improvement.DiscussionAlthough small, our case series showed a low long-term complication rate with the use of surgical mesh, compared with the majority of case series that demonstrate a re-operation rate>70%, as well as numerous cases of mesh removal. Thus, it is our experience that suburethral slings continue to be an adequate UI management option.ConclusionsSuburethral slings are a safe and effective option in UI management

Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory

Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius $A$. Also the events detected simultaneously by the surface and fluorescence detectors (the `hybrid' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.Comment: Matches published versio

The exposure of the hybrid detector of the Pierre Auger Observatory

The Pierre Auger Observatory is a detector for ultra-high energy cosmic rays. It consists of a surface array to measure secondary particles at ground level and a fluorescence detector to measure the development of air showers in the atmosphere above the array. The "hybrid" detection mode combines the information from the two subsystems. We describe the determination of the hybrid exposure for events observed by the fluorescence telescopes in coincidence with at least one water-Cherenkov detector of the surface array. A detailed knowledge of the time dependence of the detection operations is crucial for an accurate evaluation of the exposure. We discuss the relevance of monitoring data collected during operations, such as the status of the fluorescence detector, background light and atmospheric conditions, that are used in both simulation and reconstruction.Comment: Paper accepted by Astroparticle Physic

Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, \nobreak{$6\times 10^{19}$eV}. The anisotropy was measured by the fraction of arrival directions that are less than $3.1^\circ$ from the position of an active galactic nucleus within 75 Mpc (using the V\'eron-Cetty and V\'eron $12^{\rm th}$ catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is $(38^{+7}_{-6})$, compared with $21$ expected for isotropic cosmic rays. This is down from the early estimate of $(69^{+11}_{-13})$. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.Comment: Accepted for publication in Astroparticle Physics on 31 August 201