3,055 research outputs found

    Transformations between the theoretical and observational planes in the HST-NICMOS and WFPC2 photometric systems

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    Color-temperature relations and bolometric corrections in the HST-NICMOS F1110W, F160W and F222M and in the WFPC2 F439W, F555W and F814W photometric systems, using two different sets of model atmospheres, have been derived. This database of homogeneous, self-consistent transformations between the theoretical and observational planes also allows combinations of visual and infrared quantities, without any further transformation between the two different photometric systems. The behavior of the inferred quantities with varying the stellar parameters, the adopted model atmospheres and the instrumental configurations are investigated. Suitable relations to transform colors and bolometric corrections from HST to ground-based photometric systems are also provided.Comment: 22 pages, 14 figure

    Gambaran Pengetahuan Sikap dan Praktik Ibu dalam Menyediakan Konsumsi Sayur pada Anak Usia Sekolah Dasar di Semarang Tahun 2016

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    One of the foodstuffs that are essential to obtain the balance of food consumption is a vegetable. Vegetable consumption in children of school age is still very low. According to the FAO in 2010 only 63.3% of primary school age children in Indonesia who consume vegetables. Low vegetable consumption in children can lead to decreased endurance and constipation. Mothers may affect the food choices of children by providing specific food including vegetables. This study aims to describe the knowledge, attitudes and practices of mothers in providing vegetable consumption in children of the primary school in Semarang in 2016. This type of research is descriptive qualitative research with in-depth interviews. Subjects of this study amounted to 10 key informants in SD N Jabungan and 10 key informants in SD N Pendrikan Lor 03, as many as 22 people as informants triangulation which includes 20 children and two PKK. The results of the study informants in SD N Pendrikan Lor 03 has a good knowledge compared with an informant in SD N Jabungan. More than half of the informants in SD N Jabungan have a negative attitude while in SD N Pendirikan Lor 03 having a positive attitude. Practice informants in SD N Jabungan in a vegetable serving an average of 1-9 times / week. The vegetables were served less diverse and vegetable processing methods performed by the informant was still lacking. Informants in SD N Pendrikan Lor 03 in a vegetable serving an average of 10-14 times / week. Vegetable processing methods are still lacking, but in this case, the informant was much more creative in presenting vegetables for her son if it is difficult to consume vegetables is by making innovation

    Beyond Freezing: Low Temperature Lipidic Cubic Phase As Biomimetic, Nanoconfining Matrix

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    Lipidic cubic phases (LCPs) are used in areas ranging from membrane biology to drug delivery. Because some membrane proteins are notoriously unstable at room temperature, and available LCPs undergo transformation to lamellar phases at low temperatures, the development of stable low-temperature LCPs for biophysical studies of membrane proteins is called for. A family of synthetic lipids with designed cyclopropyl modifications in the hydrophobic chains was synthesised in order to study the relationship between lipid molecular structure and mesophase behaviour. These lipids show a unique liquid-crystalline behaviour at low temperatures, enabling the use of LCP crystallisation in conditions never explored before.1 Please click Additional Files below to see the full abstract

    The First Detailed Abundances for M giants in Baade's Window from Infrared Spectroscopy

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    We report the first abundance analysis of 14 M giant stars in the Galactic bulge, based on R=25,000 infrared spectroscopy (1.5-1.8um) using NIRSPEC at the Keck II telescope. Because some of the bulge M giants reach high luminosities and have very late spectral type, it has been suggested that they are the progeny of only the most metal rich bulge stars, or possibly members of a younger bulge population. We find the iron abundance and composition of the M giants are similar to those of the K giants that have abundances determined from optical high resolution spectroscopy: =-0.190 +/- 0.020 with a 1-sigma dispersion of 0.08 +/- 0.015. Comparing our bulge M giants to a control sample of local disk M giants in the Solar vicinity, we find the bulge stars are enhanced in alpha elements at the level of +0.3 dex relative to the Solar composition stars, consistent with other studies of bulge globular clusters and field stars. This small sample shows no dependence of spectral type on metallicity, nor is there any indication that the M giants are the evolved members of a subset of the bulge population endowed with special characteristics such as relative youth or high metallicity. We also find low 12C/13C < 10, confirming the prsence of extra-mixing processes during the red gaint phase of evolutionComment: 19 pages, 7 figures, accepted for publication in the Astrophysical Journa

    FbsA-driven fibrinogen polymerization: a bacterial Deceiving Strategy.

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    We show that FbsA, a cell wall protein of the bacterium Streptococcus agalactiae, promotes large-scale aggregation of human plasma fibrinogen, leading to the formation of a semiflexible polymerlike network. This extensive aggregation process takes place not only in solution, but also on FbsA-functionalized colloidal particles, and leads to the formation of a thick layer on the bacterial cell wall itself, which becomes an efficient mask against phagocytosis

    The intermediate-age globular cluster NGC 1783 in the Large Magellanic Cloud

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    We present Hubble Space Telescope ACS deep photometry of the intermediate-age globular cluster NGC 1783 in the Large Magellanic Cloud. By using this photometric dataset, we have determined the degree of ellipticity of the cluster (ϵ\epsilon=0.14±\pm0.03) and the radial density profile. This profile is well reproduced by a standard King model with an extended core (r_c=24.5'') and a low concentration (c=1.16), indicating that the cluster has not experienced the collapse of the core. We also derived the cluster age, by using the Pisa Evolutionary Library (PEL) isochrones, with three different amount of overshooting (namely, Λos\Lambda_{os}=0.0, 0.10 and 0.25). From the comparison of the observed Color-Magnitude Diagram (CMD) and Main Sequence (MS) Luminosity Function (LF) with the theoretical isochrones and LFs, we find that only models with the inclusion of some overshooting (Λos\Lambda_{os}=0.10-0.25) are able to reproduce the observables. By using the magnitude difference δVSGBHeCl=0.90\delta V_{SGB}^{He-Cl}=0.90 between the mean level of the He-clump and the flat region of the SGB, we derive an age τ\tau=1.4±\pm0.2 Gyr.Comment: Accepted to publication by A

    Red Giant stars in the Large Magellanic Cloud clusters

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    We present deep J,H,Ks photometry and accurate Color Magnitude Diagrams down to K ~18.5, for a sample of 13 globular clusters in the Large Magellanic Cloud. This data set combined with the previous sample of 6 clusters published by our group gives the opportunity to study the properties of giant stars in clusters with different ages (ranging from ~80 Myr up to ~3.5 Gyr). Quantitative estimates of star population ratios (by number and luminosity) in the Asymptotic Giant Branch, the Red Giant Branch and the He-clump, have been obtained and compared with theoretical models in the framework of probing the so-called phase transitions. The AGB contribution to the total luminosity starts to be significant at ~200 Myr and reaches its maximum at ~5-600 Myr, when the RGB Phase Transition is starting. At ~900 Myr the full developing of an extended and well populated RGB has been completed. Both the occurrence of the AGB and RGB Phase Transitions are sharp events, lasting a few hundreds Myr only. These empirical results agree very well with the theoretical predictions of simple stellar population models based on canonical tracks and the fuel-consumption approach.Comment: 32 pages, 11 figures, accepted to Ap

    A near-infrared spectroscopic screening of the red giant populations in omega Centauri

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    Near-infrared spectra of 21 giants in omega Centauri, spanning the whole range of metallicities observed in this cluster, are presented. This work is part of a coordinated photometric and spectroscopic campaign in the optical and in the infrared, aimed at studying the complex stellar population of omega Centauri and understanding its formation and chemical evolution. By analyzing the several CO and OH molecular bands and atomic lines in the spectra of the selected giants, metal abundances and abundance ratios have been obtained. The existence of three major metallicity regimes at [Fe/H]=-1.6, -1.2 and [Fe/H]<-0.5 has been confirmed. The most metal-rich stars in our sample show a lower (if any) alpha-enhancement when compared to the more metal-poor components, suggesting that they should have formed in a medium significantly polluted by type Ia supernova ejecta. Isotopic carbon abundances have been also inferred, providing an average 13C/12C=4, which clearly indicates that extra-mixing processes occurred in the stellar interiors during the ascent on the Red Giant Branch.Comment: 22 pages, 7 .ps figures. aastex. Accepted for pubilcation in the Astrophysical Journa
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