Recycling alginate composites for thermal insulation

We present a new method for the total functional recycling of alginate-based composite materials made via ionotropic gelation. The original material, an alginate/fiberglass foam with thermal insulation characteristics, was produced following a patented process in which fiberglass waste is embedded into the polyanionic gel matrix, and the resulting compound is then freeze-dried. The functional recycling is carried out by disassembling the ionic matrix \u2013 which is initially formed by the interaction between a cation (e.g. calcium) and the negatively charged alginate backbone \u2013 with the use of a chelator (Ethylenediaminetetraacetic acid disodium salt) with a high affinity for the cations, thus obtaining a homogeneous solution. An ionotropic gel can then be re-formed upon deactivation of the chelating activity under mild acid conditions. We managed to maintain or improve the thermal, mechanical and acoustic performances of the original material and we successfully tested the possibility of multiple recycling cycles

The X-Ray Zurich Environmental Study (X-ZENS). I. Chandra and XMM-Newton observations of active galactic nuclei in galaxies in nearby groups

We describe X-ray observations with Chandra and XMM-Newton of 18 galaxy groups (M_group ~ 1-6x10^13 Msolar, z~0.05) from the Zurich Environmental Study (ZENS). We aim to establish the frequency and properties, unaffected by host galaxy dilution and obscuration, of AGNs in central and satellite galaxy members, also as a function of halo-centric distance. X-ray point-source detections are reported for 22 of 177 observed galaxies, down to a limit of f_(0.5-8 keV) ~ 5x10^-15 erg cm^-2 s^-1, corresponding to a limiting luminosity of L_(0.5-8 keV)~3x10^40 erg s^-1. With the majority of the X-ray sources attributed to AGNs of low-to-moderate levels (L/L_Edd>~10^-4), we discuss the detection rate in the context of the occupation of AGNs to halos of this mass scale and redshift, and compare the structural/morphological properties between AGN-active and non-active galaxies of different rank and location within the group halos. We see a slight tendency for AGN hosts to have either relatively brighter/denser disks (or relatively fainter/diffuse bulges) than non-active galaxies of similar mass. At galaxy mass scales <10^11 Msolar, central galaxies appear to be a factor ~4 more likely to host AGNs than satellite galaxies of similar mass. This effect, coupled with the tendency for AGNs to reside in massive galaxies, explains the (weak) trend for AGNs to be preferentially found in the inner regions of groups, with no detectable trend with halo-centric distance in the frequency of AGNs within the satellite population. Finally, our data support other analyses in finding that the rate of decline with redshift of AGN activity in groups matches that of the global AGN population, indicating that either AGNs occur preferentially in groups, or that the evolution rate is independent of halo mass. These trends are of potential importance, and require X-ray coverage of a larger sample to be solidly confirmed.Comment: 18 pages, 13 figures, submitted to The Astrophysical Journal, this is a revised version that addresses the referee's comment

The Zurich Environmental Study (ZENS) of galaxies in groups along the cosmic web. V. properties and frequency of merging satellites and centrals in different environments

We use the Zurich ENvironmental Study (ZENS) database to investigate the environmental dependence of the merger fraction $\Gamma$ and merging galaxy properties in a sample of ~1300 group galaxies with $M>10^{9.2}M_\odot$ and 0.05<z<0.0585. In all galaxy mass bins investigated in our study, we find that $\Gamma$ decreases by a factor of ~2-3 in groups with halo masses $M_{HALO}>10^{13.5} M_\odot$ relative to less massive systems, indicating a suppression of merger activity in large potential wells. In the fiducial case of relaxed groups only, we measure a variation $\Delta\Gamma/\Delta \log (M_{HALO}) \sim - 0.07$ dex$^{-1}$, which is almost independent of galaxy mass and merger stage. At galaxy masses $>10^{10.2} M_\odot$, most mergers are dry accretions of quenched satellites onto quenched centrals, leading to a strong increase of $\Gamma$ with decreasing group-centric distance at these mass scales.Both satellite and central galaxies in these high mass mergers do not differ in color and structural properties from a control sample of nonmerging galaxies of equal mass and rank. At galaxy masses $<10^{10.2} M_\odot$, where we mostly probe satellite-satellite pairs and mergers between star-forming systems, close pairs (projected distance $<10-20$ kpc) show instead $\sim2\times$ enhanced (specific) star formation rates and $\sim1.5\times$ larger sizes than similar mass, nonmerging satellites. The increase in both size and SFR leads to similar surface star-formation densities in the merging and control-sample satellite populations.Comment: Published in ApJ, 797, 12

An engineering insight into the relationship of selective cytoskeletal impairment and biomechanics of HeLa cells

It is widely accepted that the pathological state of cells is characterized by a modification of mechanical properties, affecting cellular shape and viscoelasticity as well as adhesion behaviour and motility. Thus, assessing these parameters could represent an interesting tool to monitor disease development and progression, but also the effects of drug treatments. Since biomechanical properties of cells are strongly related to cytoskeletal architecture, in this work we extensively studied the effects of selective impairments of actin microfilaments and microtubules on HeLa cells through force-deformation curves and stress relaxation tests with atomic force microscopy. Confocal microscopy was also used to display the effects of the used drugs on the cytoskeletal structure. In synergy with the aforementioned methods, stress relaxation data were used to assess the storage and loss moduli, as a complementary way to describe the influence of cytoskeletal components on cellular viscoelasticity. Our results indicate that F-actin and microtubules play a complementary role in the cell stiffness and viscoelasticity, and both are fundamental for the adhesion properties. Our data support also the application of biomechanics as a tool to study diseases and their treatments

Looking ahead to the sky with the Square Kilometre Array: simulating flux densities & resolved radio morphologies of 0<z<2.50<z<2.5 star-forming galaxies

SKA-MID surveys will be the first in the radio domain to achieve clearly sub-arcsecond resolution at high sensitivity over large areas, opening new science applications for galaxy evolution. To investigate the potential of these surveys, we create simulated SKA-MID images of a $\sim$0.04 deg$^{2}$ region of GOODS-North, constructed using multi-band HST imaging of 1723 real galaxies containing significant substructure at $0<z<2.5$. We create images at the proposed depths of the band 2 wide, deep and ultradeep reference surveys (RMS = 1.0 $\mu$Jy, 0.2 $\mu$Jy and 0.05 $\mu$Jy over 1000 deg$^{2}$, 10-30 deg$^{2}$ and 1 deg$^{2}$ respectively), using the telescope response of SKA-MID at 0.6" resolution. We quantify the star-formation rate - stellar mass space the surveys will probe, and asses to which stellar masses they will be complete. We measure galaxy flux density, half-light radius ($R_{50}$), concentration, Gini (distribution of flux), second-order moment of the brightest pixels ($M_{20}$) and asymmetry before and after simulation with the SKA response, to perform input-output tests as a function of depth, separating the effects of convolution and noise. We find that the recovery of Gini and asymmetry is more dependent on survey depth than for $R_{50}$, concentration and $M_{20}$. We also assess the relative ranking of parameters before and after observation with SKA-MID. $R_{50}$ best retains its ranking, whilst asymmetries are poorly recovered. We confirm that the wide tier will be suited to the study of highly star-forming galaxies across different environments, whilst the ultradeep tier will enable detailed morphological analysis to lower SFRs.Comment: 25 pages, 14 figures, 1 table. Accepted for publication in MNRA

INOVAÇÕES:

INNOVACIONES: LAS TECNOLOGÍAS DIGITALES EN ESPACIOS EDUCATIVOS RESUMEN: El objetivo de este artículo es presentar contribuciones y dilemas de diferentes actores en el proceso de innovación en los espacios educativos. Para ello, buscamos comprender aspectos constitutivos que favorecen o impiden el proceso de utilización de las Tecnologías Digitales de Información y Comunicación (TDIC), investigando factores de razón sensible (MAFFESOLI, 1998) que justifican las resistencias al proceso de apropiación y uso de estas tecnologías con propósito pedagógico. La metodología para responder a ese conjunto de cuestionamientos previó la aplicación de un Grupo Focal (GF) compuesto por profesores, de diferentes regiones brasileñas, con experiencia en la formación de profesores y actuación en la Enseñanza Media. En el presente estudio se investigó las inferencias válidas y fundamentadas, a partir del análisis de los datos producidos en el Grupo, de situaciones reales, en contextos colocados por formadores de profesores para el uso de las TDIC en los espacios educativos, que podrán servir como base informativa en trabajos posteriores de naturaleza semejante. Para los actores involucrados en el proceso de innovación, desde directivos hasta estudiantes, existe resistencia, hecho que refuerza la importancia de comprender este movimiento para el diseño de cursos de formación con este enfoque. Palabras clave: Tecnología Digital, Innovación, Focus Group, Educación Continua, Hangout.INNOVATIONS: DIGITAL TECHNOLOGIES IN EDUCATIONAL SPACES ABSTRACT: The objective of this article is to present contributions and dilemmas of different actors in the process of innovation in educational spaces. For that, we sought to understand constitutive aspects that favor or impede the process of using Information and Communication Technologies (ICT), investigating factors of sensible reason (MAFFESOLI, 1998) that justify the resistance to the process of appropriation and use of these technologies with purpose pedagogical. The methodology for answering to this set of questions was provided with the application of a Focal Group (FG) composed of teachers, from different Brazilian regions, with experience in teacher training and performance in High School. The Hangout tool was considered as a means of realizing the virtual FG, mediated by ICT. This study investigated the valid and reasoned inferences, based on the analysis of the data produced in the Group, of real situations, in contexts placed by teacher trainers for the use of ICT in the educational spaces, which could serve as a database in later works of a same nature. The results of the study indicate that resources exist, however, they are little used in function of the quality of the continuous formation that, in the majority, does not attend to the pedagogical purposes as an example of the practices to be developed in the educative spaces; For the actors involved in the innovation process, from school principals to students, resistance looms, a fact that reinforces the importance of understanding this movement. Keywords: Digital technology, Innovation, Focus Group, Continuing Education, Hangout. &nbsp;objetivo deste artigo é apresentar contribuições e dilemas de diferentes atores no processo de inovação em espaços educativos. Para tanto, buscamos compreender aspectos constitutivos que favorecem ou impedem o processo de inovação pedagógica com a utilização das Tecnologias Digitais de Informação e Comunicação (TDIC), investigando fatores de razão sensível (MAFFESOLI, 1998) que justificam as resistências ao processo de apropriação e uso destas tecnologias com propósito pedagógico. A metodologia para responder a esse conjunto de questionamentos previu a aplicação de um Grupo Focal (GF) composto por professores, de diferentes regiões brasileiras, com experiência na formação de professores e atuação no Ensino Médio. Foi considerada como meio de realização do GF virtual, mediado por TDIC, a ferramenta Hangout. Desse estudo, investigou-se as inferências válidas e fundamentadas, a partir da análise dos dados produzidos no Grupo, de situações reais, em contextos colocados por formadores de professores para o uso das TDIC em espaços educativos, que podem servir como base informativa em trabalhos posteriores de natureza semelhante. Os resultados do trabalho apontam que os recursos existem, no entanto, são pouco utilizados em função da qualidade da formação continuada que, em sua maioria, não atende aos propósitos pedagógicos como exemplo das práticas a serem desenvolvidas nos espaços educativos. Para os atores envolvidos no processo de inovação, desde gestores até alunos, pairam resistências, fato que reforça a importância da compreensão desse movimento para o desenho das formações com esse foco. Palavras-chave: Tecnologia Digital, Inovação, Grupo Focal, Formação Continuada, Hangout. &nbsp

Indagine propedeutica allo sviluppo di un intervento di sistema sul territorio regionale nell&#8217;ambito dell&#8217;assistenza familiare

Questo rapporto si colloca in attuazione della DGR del 12.12.2016 n. 8-4336 relativa all\u2019approvazione dell\u2019Atto di indirizzo contenente criteri e modalit\ue0 per l\u2019attuazione di un intervento a favore dell\u2019Assistenza familiare che aveva \u201c[\u2026] l\u2019obiettivo sia di proseguire nel percorso intrapreso di sostegno al consolidamento della rete di strutture pubbliche e private che operano nell\u2019area dell\u2019assistenza familiare, valorizzando le esperienza positive realizzate con risorse pubbliche e private, sia di adeguare il modello regionale al mutato contesto economico-sociale e normativo attraverso una sua rivisitazione e innovazione\u201d. Nello specifico il raggiungimento degli obiettivi riportati \ue8 avvenuto attraverso la realizzazione di un\u2019indagine che ha approfondito le esperienze realizzate dal 2010 ad oggi da soggetti pubblici e privati nell\u2019ambito dell\u2019assistenza familiare. Tale indagine ha avuto luogo da luglio a novembre 2017 ed \ue8 stata effettuata da Studio Errepi Srl e dal Laboratorio Percorsi di secondo welfare. Il presente Rapporto rende conto dell\u2019indagine e riporta le esperienze pi\uf9 significative individuate e gli elementi principali che hanno contraddistinto le iniziative in termini di efficacia e sostenibilit\ue0

THE X-RAY ZURICH ENVIRONMENTAL STUDY (X-ZENS). II. X-RAY OBSERVATIONS OF THE DIFFUSE INTRAGROUP MEDIUM IN GALAXY GROUPS

We present the results of a pilot XMM-Newton and Chandra program aimed at studying the diffuse intragroup medium (IGM) of optically selected nearby groups from the Zurich ENvironmental Study (ZENS) catalog. The groups are in a narrow mass range about 10(13) M-circle dot, a mass scale at which the interplay between the IGM and the group member galaxies is still largely unprobed. X-ray emission from the IGM is detected in the energy band 0.5-2 keV with fluxPeer reviewe

A Survey of Atomic Carbon [C I] in High-redshift Main-Sequence Galaxies

We present the first results of an ALMA survey of the lower fine structure line of atomic carbon [C I](^3P_1\,-\,^{3}P_0) in far infrared-selected galaxies on the main sequence at $z\sim1.2$ in the COSMOS field. We compare our sample with a comprehensive compilation of data available in the literature for local and high-redshift starbursting systems and quasars. We show that the [C I]($^3P_1$$\rightarrow$$^3P_0$) luminosity correlates on global scales with the infrared luminosity $L_{\rm IR}$ similarly to low-$J$ CO transitions. We report a systematic variation of L'_{\rm [C\,I]^3P_1\,-\, ^3P_0}/$L_{\rm IR}$ as a function of the galaxy type, with the ratio being larger for main-sequence galaxies than for starbursts and sub-millimeter galaxies at fixed $L_{\rm IR}$. The L'_{\rm [C\,I]^3P_1\,-\, ^3P_0}/$L'_{\rm CO(2-1)}$ and $M_{\rm{[C I]}}$/$M_{\rm dust}$ mass ratios are similar for main-sequence galaxies and for local and high-redshift starbursts within a 0.2 dex intrinsic scatter, suggesting that [C I] is a good tracer of molecular gas mass as CO and dust. We derive a fraction of $f_{\rm{[C\,I]}} = M_{\rm{[C\,I]}} / M_{\rm{C}}\sim3-13$% of the total carbon mass in the atomic neutral phase. Moreover, we estimate the neutral atomic carbon abundance, the fundamental ingredient to calibrate [C I] as a gas tracer, by comparing L'_{\rm [C\,I]^3P_1\,-\, ^3P_0} and available gas masses from CO lines and dust emission. We find lower [C I] abundances in main-sequence galaxies than in starbursting systems and sub-millimeter galaxies, as a consequence of the canonical $\alpha_{\rm CO}$ and gas-to-dust conversion factors. This argues against the application to different galaxy populations of a universal standard [C I] abundance derived from highly biased samples.Comment: 14 pages + Appendix. Accepted for publication in ApJ. All the data tables in Appendix will be also released in electronic forma

The Suppression of Star Formation and the Effect of Galaxy Environment in Low-Redshift Galaxy Groups

Understanding the interaction between galaxies and their surroundings is central to building a coherent picture of galaxy evolution. Here we use GALEX imaging of a statistically representative sample of 23 galaxy groups at z=0.06 to explore how local and global group environment affect the UV properties and dust-corrected star formation rates of their member galaxies. The data provide star formation rates out to beyond 2R_200 in all groups, down to a completeness limit and limiting galaxy stellar mass of 0.06 M_sun/yr and 10^8 M_sun, respectively. At fixed galaxy stellar mass, we find that the fraction of star-forming group members is suppressed relative to the field out to an average radius of R ~ 1.5 Mpc ~ 2R_200, mirroring results for massive clusters. For the first time we also report a similar suppression of the specific star formation rate within such galaxies, on average by 40% relative to the field, thus directly revealing the impact of the group environment in quenching star formation within infalling galaxies. At fixed galaxy density and stellar mass, this suppression is stronger in more massive groups, implying that both local and global group environment play a role in quenching. The results favor an average quenching timescale of at least ~2 Gyr and strongly suggest that a combination of tidal interactions and starvation is responsible. Despite their past and ongoing quenching, galaxy groups with more than four members still account for at least ~25% of the total UV output in the nearby universe.Comment: 15 pages, 13 figures. ApJ accepte