We present the Bidimensional Exploration of the warm-Temperature Ionised gaS (BETIS) project, designed for the spatial and spectral study of the diffuse ionised gas (DIG) in a selection of nearby ...spiral galaxies observed with the MUSE integral-field spectrograph. Our primary objective is to investigate the various ionisation mechanisms at play within the DIG. We analysed the distribution of high- and low-ionisation species in the optical spectra of the sample on a spatially resolved basis. We introduced a new methodology for spectroscopically defining the DIG, optimised for galaxies of different resolutions. Firstly, we employed an innovative adaptive binning technique on the observed datacube based on the spectroscopic signal-to-noise ratio (S/N) of the collisional S II line to increase the S/N of the rest of the lines including O III , O I , and He I . Subsequently, we created a DIG mask by eliminating the emissions associated with both bright and faint H II regions. We also examined the suitability of using H α equivalent width (EW H α ) as a proxy for defining the DIG and its associated ionisation regime. Notably, for EW H α < 3 Å – the expected emission from hot low-mass evolved stars (HOLMES) – the measured value is contingent on the chosen population synthesis technique performed. Our analysis of the showcase sample reveals a consistent cumulative DIG fraction across all galaxies in the sample, averaging around 40%–70%. The average radial distribution of the N II /H α , S II /H α , O I /H α , and O III /H β ratios are enhanced in the DIG regimes (up to 0.2 dex). It follows similar trends between the DIG regime and the H II regions, as well as the H α surface brightness (Σ H α ), indicating a correlation between the ionisation of these species in both the DIG and the H II regions. The DIG loci in typical diagnostic diagrams are found, in general, within the line ratios that correspond to photoionisation due to the star formation. There is a noticeable offset correspondent to ionisation due to fast shocks. However, an individual diagnosis performed for each galaxy reveals that all the DIG in these galaxies can be attributed to photoionisation from star formation. The offset is primarily due to the contribution of Seyfert galaxies in our sample, which is closely aligned with models of ionisation from fast shocks and galactic outflows, thus mimicking the DIG emission. Our results indicate that galaxies exhibiting active galactic nucleus (AGN) activity should be considered separately when conducting a general analysis of the DIG ionisation mechanisms, since this emission is indistinguishable from high-excitation DIG.
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The basic chemical composition and calorific value of 19 samples of pine sawdust from different forest industries located in five states of the Mexican Republic (Chihuahua, Michoacán, Durango, ...Oaxaca, and Nuevo León) were determined. The results obtained ranged as follows: total extractives (6.1% to 23.4%), holocellulose (60.1% to 70.4%), lignin (20.5% to 25.8%), ash (0.27% to 0.95%), pH (4.1 to 5.3), and calorific value (20.1 MJ/kg to 21.0 MJ/kg). Except for the ash content, significant statistical differences were found according to the origin of the pine sawdust samples. Based on the results obtained, the sawdust biomass has the potential to obtain densified solid biofuels.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•Experimental study of the liquid-liquid equilibrium of glycerol-acetone-biodiesel.•Comparison of theoretical-experimental results on liquid-liquid equilibrium.•Glycerol purification process.
Getting ...high purity glycerol at a low cost from biodiesel (methylricinoleate) production is of great economic interest. Therefore, exist several strategies for raw glycerol purification. Some involve liquid-liquid extraction steps using ether, toluene, n-butanol, cyclohexanol, aniline, or solvent mixtures to remove organic impurities from glycerol. However, the phase's equilibrium data is not available for the convenient process design in some cases. This work purified raw glycerol obtained from the alkaline methanolysis of castor oil by neutralization, filtration, distillation, wash with acetone, adsorption with activated charcoal, and drying with sodium sulfate. Furthermore, liquid-liquid equilibrium (LLE) of the ternary system glycerol-acetone-biodiesel was monitored by 1H NMR spectroscopy at 281.15, 290.15, and 299.15 K and correlated by the NRTL model. Finally, we evaluated the COSMO-RS implicit solvation model predictive methodology due to the lack of LLE data for glycerol purification systems in the literature. The experimental results indicate that the process produces glycerol at 96.42% purity wt., and the LLE evaluated consists of two pairs of partially miscible liquids, glycerol-biodiesel, and glycerol-acetone. Therefore, the glycerol purification with acetone proposed here allows less process dangerous conditions, a less toxic product for food applications, eliminates 100% of organic impurities with low volumetric ratios, and helps to precipitate the persistent ash content. The theoretical results indicate COSMO-RS model overestimated the solubility glycerol-acetone, predicting only the pair of partially miscible liquids glycerol-biodiesel, this limiting the accuracy of COSMO-RS to predict LLE data for glycerol purification systems with acetone.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Numerical simulations of minor mergers predict little enhancement in the global star formation activity. However, it is still unclear the impact they have on the chemical state of the whole galaxy ...and on the mass build-up in the galaxy bulge and disc. We present a two-dimensional analysis of NCG 310, currently undergoing an intense starburst likely caused by a recent minor interaction, using data from the PPAK Integral Field Spectroscopy Nearby Galaxies Survey (PINGS). With data from a large sample of about a hundred H ii regions identified throughout the disc and spiral arms, we derive, using strong-line metallicity indicators and direct derivations, a rather flat gaseous abundance gradient. Thus, metal mixing processes occurred, as in observed galaxy interactions. Spectra from PINGS data and additional multiwavelength imaging were used to perform a spectral energy distribution fitting to the stellar emission and a photoionization modelling of the nebulae. The ionizing stellar population is characterized by single populations with a narrow age range (2.5-5 Myr) and a broad range of masses (10...-6 x 10... M...). The effect of dust grains in the nebulae is important, indicating that 25-70 per cent of the ultraviolet photons can be absorbed by dust. The ionizing stellar population within the H ii regions represents typically a few per cent of the total stellar mass. This ratio, a proxy to the specific star formation rate, presents a flat or negative radial gradient. Therefore, minor interactions may indeed play an important role in the mass build-up of the bulge. (ProQuest: ... denotes formulae/symbols omitted.)
Cell spreading and phagocytosis are notably regulated by small GTPases and GAP proteins. TBC1D10C is a dual inhibitory protein with GAP activity. In immune cells, TBC1D10C is one of the elements ...regulating lymphocyte activation. However, its specific role in macrophages remains unknown. Here, we show that TBC1D10C engages in functions dependent on the cytoskeleton and plasma membrane reorganization. Using ex vivo and in vitro assays, we found that elimination and overexpression of TBC1D10C modified the cytoskeletal architecture of macrophages by decreasing and increasing the spreading ability of these cells, respectively. In addition, TBC1D10C overexpression contributed to higher phagocytic activity against Burkholderia cenocepacia and to increased cell membrane tension. Furthermore, by performing in vitro and in silico analyses, we identified 27 TBC1D10C-interacting proteins, some of which were functionally classified as protein complexes involved in cytoskeletal dynamics. Interestingly, we identified one unreported TBC1D10C-intrinsically disordered region (IDR) with biological potential at the cytoskeleton level. Our results demonstrate that TBC1D10C shapes macrophage activity by inducing reorganization of the cytoskeleton-plasma membrane in cell spreading and phagocytosis. We anticipate our results will be the basis for further studies focused on TBC1D10C. For example, the specific molecular mechanism in Burkholderia cenocepacia phagocytosis and functional analysis of TBC1D10C-IDR are needed to further understand its role in health and disease.
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ABSTRACT
We here study the multiband properties of a kiloparsec-size superbubble in the late-type spiral galaxy NGC 628. The superbubble is the largest of many holes seen in the early release images ...using James Webb Space Telescope (JWST)/MIRI filters that trace the polycyclic aromatic hydrocarbon (PAH) emissions. The superbubble is located in the interarm region ∼3 kpc from the Galactic Centre in the south-east direction. The shell surrounding the superbubble is detected in H i, CO, and H α with an expansion velocity of 12 km s−1 and contains as much as 2 × 107 M⊙ of mass in gas that is mostly in molecular form. We find a clear excess of blue, bright stars inside the bubble as compared to the surrounding disc on the Hubble Space Telescope/Advanced Camera for Surveys images. These excess blue, bright stars are part of a stellar population of 105 M⊙ mass that is formed over the last 50 Myr in different star formation episodes, as determined from an analysis of colour–magnitude diagrams using a Bayesian technique. The mechanical power injected by the massive stars of these populations is sufficient to provide the energy necessary for the expansion of the shell gas. Slow and steady, rather than violent, injection of energy is probably the reason for the maintenance of the shell structure over the kiloparsec scale. The expanding shell is currently the site for triggered star formation as inferred from the JWST 21 µm (F2100W filter) and the H α images.
Context.
The H
II
regions are all studied employing the same general prescriptions and models, independently of the regions location in the galaxy disk. However, observed discrepancies between ...physical properties of inner and outer regions may indicate systematic differences in their star formation processes due to the influence of their environments.
Aims.
Through the analysis of inner and outer H
II
region observed spectra, we aim to explore possible systematic differences between the physical properties (metallicity, mass, and age) of their ionising clusters in order to study how star formation proceeds in different environments.
Methods.
We analysed two samples of 725 inner and 671 outer regions, characterised in the first paper of this series. Their functional parameters (oxygen abundances, ionisation parameters, and effective temperatures) were estimated and this parameter grid is employed as input for the computation of 540 Cloudy photoionisation models. Observed regions are compared with model predictions using diagnostic and evolutionary diagrams.
Results.
Higher metallicities are confirmed for the inner regions, although there are important discrepancies between the diagnostic diagrams. Calibrations based on the N2 index may underestimate inner regions oxygen abundances due to the N
II
saturation at solar metallicities. The degeneracy between the age and ionisation parameter affects oxygen abundance calibrations based on the O3N2 index. Innermost regions seem to have enhanced N/O ratios with respect to the expected values considering secondary production of nitrogen, which indicate an increase in the slope of the relation between N/O and O/H. Ionisation parameter calibrations based on the S
II
/H
α
ratio are not valid for inner regions due to the observed bivalued behaviour of this ratio with O/H. Innermost regions have lower O
II
/O
III
ratio values than expected, indicating a possible non-linear relation between
u
and
Z
. Composite stellar populations (ionising and non-ionising) are present in both inner and outer regions, with an ionising contribution of around 1%. In considering the effects of evolution and underlying populations, inner regions show larger ionising cluster masses that possibly compose star-forming complexes. The most conservative lower limit for ionising cluster masses of outer regions indicate that they might be affected by stochastic effects. Equivalent widths indicate younger ages for outer regions, but degeneracy between evolution and underlying population effects prevent a quantitative determination. Nebular properties of the H
II
regions are also derived: inner regions have larger angular sizes, lower filling factors, and larger ionised hydrogen masses.
Conclusions.
Systematic physical differences are confirmed between ionising clusters of inner and outer H
II
regions. These differences condition the validity and range of reliability of oxygen abundance and ionisation parameter calibrations commonly applied to the study of H
II
regions.
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Context. The morphological, spectroscopic, and kinematical properties of the warm interstellar medium (wim) in early-type galaxies (ETGs) hold key observational constraints to nuclear activity and ...the buildup history of these massive, quiescent systems. This article centers on a 2D investigation of the wim component in 32 nearby (?150 Mpc) ETGs from CALIFA, complementing a previous 1D analysis of the same sample. The analysis presented here includes Ha intensity and equivalent width (EW) maps and radial profiles, diagnostic emission-line ratios, and ionized-gas and stellar kinematics. It is supplemented by t-ratio maps, which are a more efficient means to quantify the role of photoionization by the post-AGB stellar component than alternative mechanisms (e.g., AGN, low-level star formation). This study adds further observational evidence for a considerable heterogeneity among ETGs with regard to the physical properties and 2D kinematics of their extended wim component, and it clearly shows that a comprehensive understanding of these systems requires IFS studies over their entire optical extent.
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