The Stellar Mass Fundamental Plane: The virial relation and a very thin plane for slow-rotators

Early-type galaxies -- slow and fast rotating ellipticals (E-SRs and E-FRs) and S0s/lenticulars -- define a Fundamental Plane (FP) in the space of half-light radius $R_e$, enclosed surface brightness $I_e$ and velocity dispersion $\sigma_e$. Since $I_e$ and $\sigma_e$ are distance-independent measurements, the thickness of the FP is often expressed in terms of the accuracy with which $I_e$ and $\sigma_e$ can be used to estimate sizes $R_e$. We show that: 1) The thickness of the FP depends strongly on morphology. If the sample only includes E-SRs, then the observed scatter in $R_e$ is $\sim 16\%$, of which only $\sim 9\%$ is intrinsic. Removing galaxies with $M_*<10^{11}M_\odot$ further reduces the observed scatter to $\sim 13\%$ ($\sim 4\%$ intrinsic). The observed scatter increases to the $\sim 25\%$ usually quoted in the literature if E-FRs and S0s are added. If the FP is defined using the eigenvectors of the covariance matrix of the observables, then the E-SRs again define an exceptionally thin FP, with intrinsic scatter of only $5\%$ orthogonal to the plane. 2) The structure within the FP is most easily understood as arising from the fact that $I_e$ and $\sigma_e$ are nearly independent, whereas the $R_e-I_e$ and $R_e-\sigma_e$ correlations are nearly equal and opposite. 3) If the coefficients of the FP differ from those associated with the virial theorem the plane is said to be `tilted'. If we multiply $I_e$ by the global stellar mass-to-light ratio $M_*/L$ and we account for non-homology across the population by using S\'ersic photometry, then the resulting stellar mass FP is less tilted. Accounting self-consistently for $M_*/L$ gradients will change the tilt. The tilt we currently see suggests that the efficiency of turning baryons into stars increases and/or the dark matter fraction decreases as stellar surface brightness increases.Comment: 13 pages, 9 figures, 3 tables, accepted for publication in MNRA

Classical Singularities In Chaotic Atom-Surface Scattering

In this paper we show that the diffraction condition for the scattering of atoms from surfaces leads to the appearance of a distinct type of classical singularity. Moreover, it is also shown that the onset of classical trapping or classical chaos is closely related to the bifurcation set of the diffraction-order function around the surface points presenting the rainbow effect. As an illustration of this dynamic, application to the scattering of He atoms by the stepped Cu(115) surface is presented using both a hard corrugated one-dimensional wall and a soft corrugated Morse potential

Galaxy properties as revealed by MaNGA. III. Kinematic profiles and stellar population gradients in S0s

This is the third paper of a series where we study the stellar population gradients (SP; ages, metallicities, $\alpha$-element abundance ratios and stellar initial mass functions) of early type galaxies (ETGs) at $z\le 0.08$ from the MaNGA-DR15 survey. In this work we focus on the S0 population and quantify how the SP varies across the population as well as with galactocentric distance. We do this by measuring Lick indices and comparing them to stellar population synthesis models. This requires spectra with high signal-to-noise which we achieve by stacking in bins of luminosity (L$_r$) and central velocity dispersion ($\sigma_0$). We find that: 1) There is a bimodality in the S0 population: S0s more massive than $3\times 10^{10}M_\odot$ show stronger velocity dispersion and age gradients (age and $\sigma_r$ decrease outwards) but little or no metallicity gradient, while the less massive ones present relatively flat age and velocity dispersion profiles, but a significant metallicity gradient (i.e. [M/H] decreases outwards). Above $2\times10^{11}M_\odot$ the number of S0s drops sharply. These two mass scales are also where global scaling relations of ETGs change slope. 2) S0s have steeper velocity dispersion profiles than fast rotating elliptical galaxies (E-FRs) of the same luminosity and velocity dispersion. The kinematic profiles and stellar population gradients of E-FRs are both more similar to those of slow rotating ellipticals (E-SRs) than to S0s, suggesting that E-FRs are not simply S0s viewed face-on. 3) At fixed $\sigma_0$, more luminous S0s and E-FRs are younger, more metal rich and less $\alpha$-enhanced. Evidently for these galaxies, the usual statement that 'massive galaxies are older' is not true if $\sigma_0$ is held fixed.Comment: Accepted for publication in MNRAS. 15 pages, 20 figure

Following in situ photoinitiated polymerization of multifunctional acrylic monomers by fluorescence and photocalorimetry simultaneously

The photoinitiated polymerization of multifunctional (meth)acrylic monomers was simultaneously monitored in real time by fluorescence and differential scanning calorimetry. As the curing proceeds, the fluorescence emission changes due to an increase in the viscosity of the microenvironment. A good correlation between fluorescence intensity and degree of conversion was established by using two different fluorescent probes, each having the same fluorophore, dialkylamino derivatives of 7-nitro-2-oxa-1,3-diazol. One of the probes contains an acrylic moiety which can react with the monomers labelling the formed network. The use of the first moment of fluorescence is presented as a suitable methodology to avoid experimental fluctuations. Furthermore, the influence of the length of the spacer between the acrylic groups in the polymerization reaction kinetics and fluorescence changes has been also discussed in terms of reaction diffusion controlled termination kinetics and free volume fraction. It was concluded that the fluorescence method is a powerful tool to study the kinetics of photopolymerization of multifunctional monomers.The authors would like to thank the Union European Commission for funding through the BRITE-Euram Project (BE97-4472). Gratitude is also extended to Plan Nacional I+D+I (Ministerio de Ciencia y Tecnologı́a) for financial support (MAT1998-0518-CE and MAT2000-1671). We thank to Dr K. Dietliker, from Ciba Speciality Chemicals, for providing the photoinitiators. The authors are grateful to Valentı́n Guadaño from Lasing for helpful discussions regarding to the optical coupling between the calorimeter and spectrofluorimeter. J. Baselga wishes to thank CAM (PRICIT Programme)

Sampling strategies and biodiversity of influenza A subtypes in wild birds

Wild aquatic birds are recognized as the natural reservoir of avian influenza A viruses (AIV), but across high and low pathogenic AIV strains, scientists have yet to rigorously identify most competent hosts for the various subtypes. We examined 11,870 GenBank records to provide a baseline inventory and insight into patterns of global AIV subtype diversity and richness. Further, we conducted an extensive literature review and communicated directly with scientists to accumulate data from 50 non-overlapping studies and over 250,000 birds to assess the status of historic sampling effort. We then built virus subtype sample-based accumulation curves to better estimate sample size targets that capture a specific percentage of virus subtype richness at seven sampling locations. Our study identifies a sampling methodology that will detect an estimated 75% of circulating virus subtypes from a targeted bird population and outlines future surveillance and research priorities that are needed to explore the influence of host and virus biodiversity on emergence and transmission

Computationally Guided Design of a Readily Assembled Phosphite- Thioether Ligand for a Broad Range of Pd-Catalyzed Asymmetric Allylic Substitutions

A modular approach employing indene as common starting material, has enabled the straightforward preparation in three reaction steps of P-thioether ligands for the Pd-catalyzed asymmetric allylic substitution. The analysis of a starting library of P-thioether ligands based on rational design and theoretical calculations has led to the discovery of an optimized anthracenethiol derivative with excellent behavior in the reaction of choice. Improving most approaches reported to date, this ligand presents a broad substrate and nucleophile scope. Excellent enantioselectivities have been achieved for a range of linear and cyclic allylic substrates using a large number of C-, N-, and O-nucleophiles (40 compounds in total). The species responsible for the catalytic activity have been further investigated by NMR in order to clearly establish the origin of the enantioselectivity. The resulting products have been derivatized by means of ring-closing metathesis or Pauson–Khand reactions to further prove the synthetic versatility of the methodology for preparing enantiopure complex structures

Ensayos de secado de nopalito (<i>Opuntia Ficus indica L.Millar</i>) en un secador solar pasivo de uso doméstico

El nopal (Opuntia Ficus indica), es una especie vegetal nativa de América, perteneciente a la familia de las cactáceas, con presencia a lo largo de todo el continente, encontrándose en nuestro país con predominio en las provincias del centro y norte en forma silvestre, introduciéndose durante el año 2006 en el Valle de Lerma, Salta como hortaliza alternativa (Lozano et at., 2007). Su uso como alimento se encuentra arraigado en México, donde se consumen las hojas (pencas) frescas o procesadas y los frutos (tunas), consumidos frescos o en dulces y licuados. Además, por su contenido en fibra, su utilización en la industria alimentaria representa una alternativa para la formulación de alimentos funcionales (harinas enriquecidas). La harina de nopalito se caracteriza por su elevado contenido en fibra alimentaria (FA) y minerales entre los que se destaca el calcio. Diversos estudios epidemiológicos demuestran que el consumo de FA produce una mayor motilidad intestinal, interviniendo en la prevención de la constipación, regulación de glucosa y lípidos en sangre. Para que la FA pueda ejercer su efecto fisiológico en el ser humano deben de mantenerse intactas algunas de sus propiedades físico-químicas como son su viscosidad, capacidad de absorción de agua y aceite. En este trabajo se estudia el secado de muestras de nopalitos, empleando un secador solar de pequeña escalan de tipo pasivo, donde la circulación de aire se produce mediante una chimenea concentrador CPC, (Durán, et al. 2008). Se analiza la influencia de las variables ambientales como la radiación solar y la temperatura ambiente en el proceso de secado del nopal, como así también en la calidad del producto seco.The nopal (Opuntia ficus), is a native American plant species, belonging to the family of cacti, with a presence throughout the American continent. In Argentina it´s found as native flora in the northern and central provinces. It was introduced as alternative crop in 2006 in the Valle de Lerma, Salta as a vegetable alternative (Lozano et at., 2007). Its use as food is rooted in Mexico, where they are consumed leaves (fronds) and fresh or processed fruits (tunas), consumed fresh or in sweet and smoothies. In addition, fiber content, its use in the food industry is an alternative for the formulation of functional foods (enriched flour). Nopalito flour is characterized by its high content of dietary fiber (FA) and minerals including calcium stands. Epidemiological studies show that consumption of FA produces greater motility, intervening in the prevention of constipation, regulation of glucose and blood lipids. For the FA can exert its physiological effect on humans must be kept intact some of its physicochemical properties such as viscosity, water absorption capacity and oil. This paper studies the dried cactus samples, using a solar dryerfor small scale passive type, where the airflow is produced by a fireplace concentrator CPC (Duran et al. 2008). We analyze theinfluence of environmental variables such as solar radiation and temperature in the drying of cactus, as well as the quality of dried product.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Phytoplankton dynamics in relation to seasonal variability and upwelling and relaxation patterns at the mouth of Ria de Aveiro (West Iberian Margin) over a four-year period

From June 2004 to December 2007, samples were weekly collected at a fixed station located at the mouth of Ria de Aveiro (West Iberian Margin). We examined the seasonal and inter-annual fluctuations in composition and community structure of the phytoplankton in relation to the main environmental drivers and assessed the influence of the oceano-graphic regime, namely changes in frequency and intensity of upwelling events, over the dynamics of the phytoplankton assemblage. The samples were consistently handled and a final subset of 136 OTUs (taxa with relative abundance > 0.01%) was subsequently submitted to various multivariate analyses. The phytoplankton assemblage showed significant changes at all temporal scales but with an overriding importance of seasonality over longer-(inter-annual) or shorter-term fluctuations (upwelling-related). Sea-surface temperature, salinity and maximum upwelling index were retrieved as the main driver of seasonal change. Seasonal signal was most evident in the fluctuations of chlorophyll a concentration and in the high turnover from the winter to spring phytoplankton assemblage. The seasonal cycle of production and succession was disturbed by upwelling events known to disrupt thermal stratification and induce changes in the phytoplankton assemblage. Our results indicate that both the frequency and intensity of physical forcing were important drivers of such variability, but the outcome in terms of species composition was highly dependent on the available local pool of species and the timing of those events in relation to the seasonal cycle. We conclude that duration, frequency and intensity of upwelling events, which vary seasonally and inter-annually, are paramount for maintaining long-term phytoplankton diversity likely by allowing unstable coexistence and incorporating species turnover at different scales. Our results contribute to the understanding of the complex mechanisms of coastal phytoplankton dynamics in relation to changing physical forcing which is fundamental to improve predictability of future prospects under climate change.Portuguese Foundation for Science and Technology (FCT, Portugal) [SFRH/BPD/ 94562/2013]; FEDER funds; national funds; CESAM [UID/AMB/50017]; FCT/MEC through national funds; FEDERinfo:eu-repo/semantics/publishedVersio