Bulges and disks in the local Universe. Linking the galaxy structure to star formation activity

We use a sample built on the SDSS DR7 catalogue and the bulge-disc decomposition of Simard et al. (2011) to study how the bulge and disc components contribute to the parent galaxy's star formation activity, by determining its position in the star formation rate (SFR) - stellar mass (M$_{\star}$) plane at 0.02$<z<$0.1. We use the bulge and disc colours as proxy for their SFRs. We study the mean galaxy bulge-total mass ratio (B/T) as a function of the residual from the MS ($\Delta_{MS}$) and find that the B/T-$\Delta_{MS}$ relation exhibits a parabola-like shape with the peak of the MS corresponding to the lowest B/Ts at any stellar mass. The lower and upper envelop of the MS are populated by galaxies with similar B/T, velocity dispersion and concentration ($R_{90}/R_{50}$) values. Bulges above the MS are characterised by blue colours or, when red, by a high level of dust obscuration, thus indicating that in both cases they are actively star forming. When on the MS or below it, bulges are mostly red and dead. At stellar masses above $10^{10.5}$M$_{\odot}$, bulges on the MS or in the green valley tend to be significantly redder than their counterparts in the quiescence region, despite similar levels of dust obscuration. The disc color anti-correlates at any mass with the distance from the MS, getting redder when approaching the MS lower envelope and the quiescence region. We conclude that the position of a galaxy in the LogSFR-LogM$_{\star}$ plane depends on the star formation activity of its components: above the MS both bulge and disk are actively star forming. The nuclear activity is the first to be suppressed, moving the galaxies on the MS. Once the disk stops forming stars as well, the galaxy moves below the MS and eventually to the quiescence region. This is confirmed by a large fraction ($\sim45\%$) of passive galaxies with a secure two component morphology.Comment: Version modified after referee comment

Antimatter research in Space

Two of the most compelling issues facing astrophysics and cosmology today are to understand the nature of the dark matter that pervades the universe and to understand the apparent absence of cosmological antimatter. For both issues, sensitive measurements of cosmic-ray antiprotons and positrons, in a wide energy range, are crucial. Many different mechanisms can contribute to antiprotons and positrons production, ranging from conventional reactions up to exotic processes like neutralino annihilation. The open problems are so fundamental (i.e.: is the universe symmetric in matter and antimatter ?) that experiments in this field will probably be of the greatest interest in the next years. Here we will summarize the present situation, showing the different hypothesis and models and the experimental measurements needed to lead to a more established scenario.Comment: 10 pages, 7 figures, Invited talk at the 18th European Cosmic Ray Symposium, Moscow, July 2002, submitted to Journal of Physics

Light-harvesting antennae based on copper indium sulfide (CIS) quantum dots

Copper indium sulfide quantum dots (CIS QDs) and their core-shell analogues (CIS@ZnS QDs) were functionalized with pyrene chromophores via a dihydrolipoamide bifunctional binding moiety: UV excitation of the pyrene chromophores resulted in sensitized emission of the CIS core because of an efficient energy transfer process; the core-shell hybrid system exhibits a 50% increased brightness when excited at 345 nm

Anticoagulant pseudothrombocytopenia with platelet satellitism

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A reanalysis of the atmospheric boundary layer field experiment(SPCFLUX93) at San Pietro Capofiume (Italy)

A fortnight field experiment was carried out at San Pietro Capofiume(Po Valley, Italy)during the month of June, 1993, and was named SPCFLUX93. This location was chosen as representative of the Po Valley. The SPCFLUX93 experiment was devised according to the results of some previous measurements carried out in mountainous areas of South Europe (i.e. ALPEX—ALPine EXperiment, PYREX—PYRenean Experiment), and aimed to represent a prototype for further field observations. The dataset of the SPCFLUX93 experiment consisted of: i)meteorological and chemical data collected continuously with slow-response sensors in the atmospheric surface layer and into the soil; ii)data coming from fastresponse instrumentation (sonic anemometers and fluxmeter); iii) radiosoundings carried out with free and tethered balloons; iv)con tinuous vertical wind soundings with a Mini-Sodar. The aim of the SPCFLUX93 field experiment was to investigate the following topics: atmospheric turbulence, dry and wet atmospheric total deposition, energy balance, thermal wave propagation in the soil. Few years later, the atmospheric and hydrological scientific community conduced an extensive programme, the Mesoscale Alpine Programme (MAP), on weather and climate in mountainous regions. This programme considered many aspects of alpine meteorology, ranging from high-resolution numerical modelling to experimental campaigns performed on both sides of the Alps, with the aim to better understand the interaction processes of atmospheric fluxes with the orography. Many puzzling problems were posed by the complexity of these interactions; among them, the perturbations on the boundary layer structure caused by the airflows that cross the Alps and reach the Po Valley would still require more experimental observations and theoretical studies. These considerations prompted us to reanalyze the SPCFLUX93 dataset. In this paper, a layout of the field experiment (including the instrumentation details, the experimental relevant dataset and database composed by meteorological standard data, vertical profile data, ultrasonic anemometer data, and chemical data)is presented; the collected data are described; the details of the mesoscale meteorological situation over San Pietro Capofiume during the experiment are presented; finally, some analyses on the data are shown, and the main results coming from the several applications carried out using the dataset are illustrated or summarized. In particular, the most interesting results are related to the following topics: the characteristics of the turbulence in the surface layer (using the fast-response data), the validation of land surface schemes (using the surface observations), the evaluation of mixed layer depth (using radon flux data)and the estimate of deposition velocity