Physical Properties, Star Formation, and Active Galactic Nucleus Activity in Balmer Break Galaxies at 0 < z < 1

We present a spectroscopic study with the derivation of the physical properties of 37 Balmer break galaxies, which have the necessary lines to locate them in star-forming-AGN diagnostic diagrams. These galaxies span a redshift range from 0.045 to 0.93 and are somewhat less massive than similar samples of previous works. The studied sample has multiwavelength photometric data coverage from the ultraviolet to MIR Spitzer bands. We investigate the connection between star formation and AGN activity via optical, mass-excitation (MEx) and MIR diagnostic diagrams. Through optical diagrams, 31 (84%) star-forming galaxies, 2 (5%) composite galaxies and 3 (8%) AGNs were classified, whereas from the MEx diagram only one galaxy was classified as AGN. A total of 19 galaxies have photometry available in all the IRAC/Spitzer bands. Of these, 3 AGN candidates were not classified as AGN in the optical diagrams, suggesting they are dusty/obscured AGNs, or that nuclear star formation has diluted their contributions. Furthermore, the relationship between SFR surface density (\Sigma_{SFR}) and stellar mass surface density per time unit (\Sigma_{M_{\ast}/\tau}) as a function of redshift was investigated using the [OII] \lambda3727, 3729, H\alpha \lambda6563 luminosities, which revealed that both quantities are larger for higher redshift galaxies. We also studied the SFR and SSFR versus stellar mass and color relations, with the more massive galaxies having higher SFR values but lower SSFR values than less massive galaxies. These results are consistent with previous ones showing that, at a given mass, high-redshift galaxies have on average larger SFR and SSFR values than low-redshift galaxies. Finally, bluer galaxies have larger SSFR values than redder galaxies and for a given color the SSFR is larger for higher redshift galaxies.Comment: preprint version, 36 pages, 17 figures, 3 tables, accepted for publication in the Astrophysical Journa

Well-posedness and asymptotic behavior of a multidimensional model of morphogen transport

Morphogen transport is a biological process, occurring in the tissue of living organisms, which is a determining step in cell differentiation. We present rigorous analysis of a simple model of this process, which is a system coupling parabolic PDE with ODE. We prove existence and uniqueness of solutions for both stationary and evolution problems. Moreover we show that the solution converges exponentially to the equilibrium in $C^1\times C^0$ topology. We prove all results for arbitrary dimension of the domain. Our results improve significantly previously known results for the same model in the case of one dimensional domain

Spillover and diffraction sidelobe contamination in a double-shielded experiment for mapping Galactic synchrotron emission

We have analyzed observations from a radioastronomical experiment to survey the sky at decimetric wavelengths along with feed pattern measurements in order to account for the level of ground contamination entering the sidelobes. A major asset of the experiment is the use of a wire mesh fence around the rim-halo shielded antenna with the purpose of levelling out and reducing this source of stray radiation for zenith-centered 1-rpm circular scans. We investigate the shielding performance of the experiment by means of a geometric diffraction model in order to predict the level of the spillover and diffraction sidelobes in the direction of the ground. Using 408 MHz and 1465 MHz feed measurements, the model shows how a weakly-diffracting and unshielded antenna configuration becomes strongly-diffracting and double-shielded as far-field diffraction effects give way to near-field ones. Due to the asymmetric response of the feeds, the orientation of their radiation fields with respect to the secondary must be known a priori before comparing model predictions with observational data. By adjusting the attenuation coefficient of the wire mesh the model is able to reproduce the amount of differential ground pick-up observed during test measurements at 1465 MHz.Comment: 14 pages, 17 eps + 1 gif figures and 4 Tables. Accepted for publication in A&AS. Fig.7 available at full resolution from http://www.das.inpe.br/~tello/publications.ht

Proximal, Microbiological and Color Evaluation and Comparison of the Meat of Llamas (Lama glama) and Alpacas (Vicugna pacos)

In this study, the meat of llama (Lama glama) and alpaca (Vicugna pacos) were examined. Data were analyzed through the analysis of variance (ANOVA) using the Centurion Statgraphics software. The bromatological characteristics of the meat were evaluated through proximal analysis. A high percentage of protein content was identified, with a higher value in the llama meat (24.025%). Regarding the ethereal extract, minimum values ​​were obtained in the alpaca meat (2.707%), indicating lean meat. The humidity was variable depending on the conditions of the conservation, and the organic matter present in the meat defined the ash content, which was not higher than 5%. In terms of the microbiological analyses, the value ​​of viable aereobic mesophiles in llama meat was 1330 cfu/g, and in alpaca meat it was 1490 cfu/g; and the values for E. coli were 0.500 cfu/g and 1,250 cfu/g, respectively. Keywords: software, Lama glama, Vicugna pacos, proximal analysis, microbiological requirements. RESUMEN La carne de Llama (Lama glama) y Alpaca (Vicugna pacos) cumple con los requisitos para ser considerada como carne; Mediante el análisis de varianza (ANOVA) utilizando el Software Statgraphics Centurion se evalúa los requisitos bromatológicos por medio del análisis proximal de las carnes en estudio, donde se identifica un alto porcentaje en el contenido de proteína, lo que conlleva a un elevado valor biológico en ambas especies, siendo más destacada, en la carne de llama con 24,025%; En cuanto a extracto etéreo&nbsp; se obtiene valores mínimos en especial en la carne de alpaca con 2,707%, favoreciendo a la obtención de carne magra; En lo referente a humedad va a ser variable dependiendo de las condiciones de conservación de la misma, mientras tanto la materia orgánica presente en la carne define el contenido de cenizas, el cual no podrá ser mayor al 5%. En relación a los análisis microbiológicos los valores de Mesófilos Aereobios Viables en la carne de llama fueron 1330 ufc/g, en la carne de alpaca 1490 ufc/g, para E. Coli &nbsp;de 0,500 ufc/g, y 1,250 ufc/g respectivamente encontrándose dentro de lo establecido en la Norma, y valores no permisibles por la presencia de Coliformes Totales.&nbsp; &nbsp; Palabras clave: software, Lama glama, Vicugna pacos, análisis proximal, requerimientos microbiológicos

From a sequential pattern, temporal adjustments emerge in hummingbird traplining

Animals that feed from resources that are constant in space and that refill may benefit from repeating the order in which they visit locations. This is a behavior known as traplining, a spatial phenomenon. Hummingbirds, like other central‐place foragers, use short traplines when moving between several rewarding sites. Here we investigated whether traplining hummingbirds also use relevant temporal information when choosing which flowers to visit. Wild rufous hummingbirds that were allowed to visit 3 artificial flower patches in which flowers were refilled 20 min after they had been depleted repeated the order in which they visited the 3 patches. Although they tended to visit the first 2 patches sooner than 20 min, they visited the third patch at approximately 20‐min intervals. The time between visits to the patches increased across the experiment, suggesting that the birds learned to wait longer before visiting a patch. The birds appeared to couple the sequential pattern of a trapline with temporal regularity, to some degree. This suggests that there is a temporal component to the repeated spatial movements flown by foraging wild hummingbirds.PostprintPeer reviewe

Impact of Fluid Substitution on the Performance of an Axial Compressor Blade Cascade Working with Supercritical Carbon Dioxide

Abstract Recent research on turbomachinery design and analysis for supercritical carbon dioxide (sCO2) power cycles has relied on computational fluid dynamics. This has produced a large number of works whose approach is mostly case-specific, rather than of general application to sCO2 turbomachinery design. As opposed to such approach, this work explores the aerodynamic performance of compressor blade cascades operating on air and supercritical CO2 with the main objective to evaluate the usual aerodynamic parameters of the cascade for variable boundary conditions and geometries, enabling “full” or “partial” similarity. The results present both the global performance of the cascades and certain features of the local flow (trailing edge and wake). The discussion also highlights the mechanical limitations of the analysis (forces exerted on the blades), which is the main restriction for applying similarity laws to extrapolate the experience gained through decades of work on air turbomachinery to the new working fluid. This approach is a step toward the understanding and appropriate formulation of a multi-objective optimization problem for the design of such turbomachinery components where sCO2 is used as the operating fluid. With this objective, the paper aims to identify and analyze what would be expected if a common description of such computational design problems similar to those where air is the working fluid were used.</jats:p

Knowledge and degree of training of Primary Education teachers in relation to ICT taught to disabled students

The integration of Information and Communication Technologies (ICT) into the inclusive classroom requires competent teaching staff from both the technological and pedagogical points of view. Within this context, and with the aim of looking at one of these theoretical premises, this study aimed to identify the degree of training and technological knowledge of primary school teachers in Spain with respect to the use of ICT with individuals with disabilities (functional diversity). A descriptive ex post-facto research method was used, where the sample comprised 777 teachers. An ad-hoc questionnaire was used as the data-collection instrument. The results revealed the low skill levels of the teachers with respect to the use of ICT with students with disabilities, where the level of training of the teaching staff was determined by personal (gender, age), professional (teaching experience) or educational (qualifications) variables. The findings of this study point to the need for teacher training that instructs teachers on the use of ICT in order to favour the learning and educational innovation of students with disabilities

Jahn-Teller EPA spectra of Cu2 + in MgSif6.6H20

The 34 GHz EPR spectrum ofCu2+ in MgSiF6-6H20 showed a "static" Jahn-Teller effect at 4.2 K with two inequivalent Jahn- Teller sites per unit cell. The six axially symmetric sets of Cu2+ lines had their z axes parallel to the three tetragonal axes of two cubes, which were rotated by approximately 40" with respect to each other about a common (Ill) axis, which is the crystal c axis. The measured spin-Hamiltonian parameters at 4.2 K for each set of lines were g11 = 2.47 ± 0.01, g1 = 2.10 ± 0.01 , and lA 11 1 = (110 ± 3)X 10- 4 em- •. There was a gradual decrease in the anisotropy of the spectrum on warming the crystal, with a single, nearly isotropic line being observed above 220 K. At 270 K the spectrum had axial symmetry about the c axis with Kn = 2.23 ± 0.01 and g~ = 2.25 ± 0.01 . The temperature evolution of the spectrum was interpreted in terms of a Boltzmann distribution over inequivalent distorted Jahn-Teller configurations, with one potential well lowered by an amount L1:::::: I 05 em- 1 below the other two

Size is relative : use of relational concepts by wild hummingbirds

This work was supported by the Association for the Study of Animal Behaviour (S.D.H.), the University of Lethbridge and the Natural Sciences and Engineering Research Council of Canada (RGPIN 121496–2003; T.A.H.).Rufous hummingbirds (Selasphorus rufus) will readily learn the location and the colour of rewarded flowers within their territory. But if these birds could apply a relational concept such as ‘the larger flowers have more nectar’, they could forego learning the locations of hundreds of individual flowers. Here, we investigated whether wild male territorial rufous hummingbirds might use ‘larger than’ and ‘smaller than’ relational rules and apply them to flowers of different sizes. Subjects were trained to feed consistently from one of two flowers. Although the flowers differed only in size, the reward was always contained in the same-size flower. The birds were then tested on a choice of two empty flowers: one of the familiar size and the other a novel size. Hummingbirds applied relational rules by choosing the flower that was of the correct relational size rather than visiting the flower of the size rewarded during training. The choices made by the hummingbirds were not consistent with alternative mechanisms such as peak shift or associative learning. We suggest that while hummingbirds are very good at remembering the spatial locations of rewarding flowers, they would be able to use relative rules when foraging in new and changing environments.Publisher PDFPeer reviewe