Ferromagnetic properties of charged vector bosons condensate in the early universe

Bose-Einstein condensation in the early universe is considered. The magnetic properties of a condensate of charged vector bosons are studied, showing that a ferromagnetic state is formed. As a consequence, the primeval plasma may be spontaneously magnetized inside macroscopically large domains and primordial magnetic fields can be generated.Comment: 4 pages IAU Symposium 274, 6-10 September 2010, Giardini Naxos, Italy; Published in Proceedings of the International Astronomical Union, 2011, Advances in Plasma Astrophysics, A. Bonanno, E. de Gouveia Dal Pino & A. Kosovichev, eds., Cambridge Univerity Pres

Electronic stopping power in gold: the role of d electrons and the H/He anomaly.

The electronic stopping power of H and He moving through gold is obtained to high accuracy using time-evolving density-functional theory, thereby bringing usual first principles accuracies into this kind of strongly coupled, continuum nonadiabatic processes in condensed matter. The two key unexplained features of what observed experimentally have been reproduced and understood: (i) The nonlinear behavior of stopping power versus velocity is a gradual crossover as excitations tail into the d-electron spectrum; and (ii) the low-velocity H/He anomaly (the relative stopping powers are contrary to established theory) is explained by the substantial involvement of the d electrons in the screening of the projectile even at the lowest velocities where the energy loss is generated by s-like electron-hole pair formation only

The Data Analysis Pipeline for the SDSS-IV MaNGA IFU Galaxy Survey: Emission-Line Modeling

SDSS-IV MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) is the largest integral-field spectroscopy survey to date, aiming to observe a statistically representative sample of 10,000 low-redshift galaxies. In this paper we study the reliability of the emission-line fluxes and kinematic properties derived by the MaNGA Data Analysis Pipeline (DAP). We describe the algorithmic choices made in the DAP with regards to measuring emission-line properties, and the effect of our adopted strategy of simultaneously fitting the continuum and line emission. The effect of random errors are quantified by studying various fit-quality metrics, idealized recovery simulations and repeat observations. This analysis demonstrates that the emission lines are well-fit in the vast majority of the MaNGA dataset and the derived fluxes and errors are statistically robust. The systematic uncertainty on emission-line properties introduced by the choice of continuum templates is also discussed. In particular, we test the effect of using different stellar libraries and simple stellar-population models on the derived emission-line fluxes and the effect of introducing different tying prescriptions for the emission-line kinematics. We show that these effects can generate large ($>$ 0.2 dex) discrepancies at low signal-to-noise and for lines with low equivalent width (EW); however, the combined effect is noticeable even for H$\alpha$ EW $>$ 6~\AA. We provide suggestions for optimal use of the data provided by SDSS data release 15 and propose refinements on the \DAP\ for future MaNGA data releases.Comment: accepted on A

Light responsive metal-organic frameworks as controllable CO-releasing cell culture substrates

A new carbon monoxide (CO)-releasing material has been developed by embedding a manganese carbonyl complex, MnBr(bpydc)(CO)3 (bpydc = 5, 5′-dicarboxylate-2, 2′-bipyridine) into a highly robust Zr(iv)-based metal-organic framework (MOF). Efficient and controllable CO-release was achieved under exposure to low intensity visible light. Size-controllable nanocrystals of the photoactive MOF were obtained and their CO-releasing properties were correlated with their crystal sizes. The photoactive crystals were processed into cellular substrates with a biocompatible polymer matrix, and the light-induced delivery of CO and its subsequent cellular uptake were monitored using a fluorescent CO-probe. The results discussed here demonstrate a new opportunity to use MOFs as macromolecular scaffolds towards CO-releasing materials and the advantage of MOFs for high CO payloads, which is essential in future therapeutic applications

Orobanche centaurina Bertol. the correct name for O. kochii F.W. Schultz (Orobanchaceae)

Después de estudiar el material original de Orobanche centaurina Bertol. (Orobanchaceae) depositado en BOLO, una olvidada especie descrita de Massa (Italia central) parásita de Centaurea paniculata L., y compararlo con el tipo de O. kochii F.W. Schultz y con los tipos de otros táxones actualmente considerados inónimos de éste, estimamos que el nombre de Bertoloni es el correcto y prioritario para esta especi

ϕ2\phi^2 as Dark Matter

In this paper we consider $\phi^2$ scalar field potential as a candidate to dark matter. If it is an ultralight boson particle, it condensates like a Bose-Einstein system at very early times and forms the basic structure of the Universe. Real scalar fields collapse in equilibrium configurations that oscillate in space-time (oscillatons).The cosmological behavior of the field equations are solved using the dynamical system formalism. We use the current cosmological parameters as constraints for the present value of the scalar field. We reproduce the cosmological predictions of the standard $\Lambda$CDM model with this model. Therefore, scalar field dark matter seems to be a good alternative to cold dark matter nature.Comment: Accepted for publication in MNRAS 11 pages, 7 figure

Maternal genetic inheritance of red pericarp in the grain of maize

The diversity of colors in the grain of corn is wide, from whites to blacks and including a continuum of various shades of yellows, pinks, reds, purples and blues. The most abundant commercial colors are yellow and white, however other colors have become more important because of the presence of pigments to which are attributed favorable effects as a food. The pigments are also considered natural barriers of the grain against the invasion of pests and diseases in the production fields. The colors of the grain of corn occur in three different parts of the seed: the cover of the grain or pericarp, derived from the maternal tissue, with a diploid genetic content; the endo-sperm, including the aleurone layers that are cells in the grain immediately below the pericarp with a chromosome content of 3n; and the embryo, with a genetic content of 2n. The red color considered in this study is present in the pericarp ignoring possible effects in other tissues of grain and other organs of the plant. In this study, we used materials with colorless or red pericarp, and white or yellow endosperm; with the purpose of describing the type of inheritance of this character in the grain of corn. The results indicated a maternal genetic inheritance with classical complete dominance of the red color of pericarp over the clear or transparent phenotype, where the red color of the grains on ear is determined by the genotype of the mother grain but not by the seed embryo genotypes, which is characterized by uniformity of grain color of the ear. This type of inheritance could be useful in the development of pigmented varieties of higher food quality for humans

Twist-4 contribution to unpolarized structure functions F_L and F_2 from instantons

We compute in the instanton vacuum the nucleon matrix elements of the twist-4 QCD operators describing power corrections to the second moments of the unpolarized structure functions, F_L and F_2. Our approach takes into account the leading contribution in the packing fraction of the instanton medium, rho / R << 1. Parametrically leading are the matrix elements of a twist-4 quark-gluon operator, which are of the order of the inverse instanton size, 1/rho^2 = (600 MeV)^2. The matrix elements of the four-fermion (diquark) operators are suppressed by a factor (rho / R)^4 and numerically small. These results are in agreement with the pattern of phenomenological 1/Q^2-corrections to R = sigma_L / sigma_T and F_2 found in QCD fits to the data. In particular, the rise of R at low Q^2 can be obtained from instanton-type vacuum fluctuations at a low scale.Comment: 38 pages, LaTeX. 4 figures included using eps

Electronic stopping power in LiF from first principles.

Using time-dependent density-functional theory we calculate from first principles the rate of energy transfer from a moving proton or antiproton to the electrons of an insulating material, LiF. The behavior of the electronic stopping power versus projectile velocity displays an effective threshold velocity of approximately 0.2 a.u. for the proton, consistent with recent experimental observations, and also for the antiproton. The calculated proton/antiproton stopping-power ratio is approximately 2.4 at velocities slightly above the threshold (v approximately 0.4 a.u.), as compared to the experimental value of 2.1. The projectile energy loss mechanism is observed to be extremely local