The properties of dwarf spheroidal galaxies in the Cen A group

Dwarf spheroidal galaxies (dSphs) have been extensively investigated in the Local Group, but their low luminosity and surface brightness make similar work in more distant galaxy groups challenging. Modern instrumentation unlocks the possibility of scrutinizing these faint systems in other environments, expanding the parameter space of group properties. We use MUSE spectroscopy to study the properties of 14 known or suspected dSph satellites of Cen A. Twelve targets are confirmed to be group members based on their radial velocities. Two targets are background galaxies at ∼50 Mpc: KK 198 is a face-on spiral galaxy, and dw1315−45 is an ultra-diffuse galaxy with an effective radius of ∼2300 pc. The 12 confirmed dSph members of the Cen A group have old and metal-poor stellar populations and follow the stellar metallicity-luminosity relation defined by the dwarf galaxies in the Local Group. In the three brightest dwarf galaxies (KK 197, KKs 55, and KKs 58), we identify globular clusters, as well as a planetary nebula in KK 197, although its association with this galaxy and/or the extended halo of Cen A is uncertain. Using four discrete tracers, we measure the velocity dispersion and dynamical mass of KK 197. This dSph appears dark matter dominated and lies on the radial acceleration relation of star-forming galaxies within the uncertainties. It also is consistent with predictions stemming from modified Newtonian dynamics. Surprisingly, in the dwarf KK 203 we find an extended Hα ring. Careful examination of Hubble Space Telescope photometry reveals a very low level of star formation at ages between 30 and 300 Myr. The Hα emission is most likely linked to a ∼40 Myr old supernova remnant, although other possibilities for its origin cannot be entirely ruled out

Less loop diuretic use in patients on sacubitril/valsartan undergoing remote pulmonary artery pressure monitoring

Aims Control of pulmonary pressures monitored remotely reduced heart failure hospitalizations mainly by lowering filling pressures through the use of loop diuretics. Sacubitril/valsartan improves heart failure outcomes and increases the kidney sensitivity for diuretics. We explored whether sacubitril/valsartan is associated with less utilization of loop diuretics in patients guided with haemodynamic monitoring in the CardioMEMS European Monitoring Study for Heart Failure (MEMS-HF). Methods and results The MEMS-HF population (n = 239) was separated by the use of sacubitril/valsartan (n = 68) or no use of it (n = 164). Utilization of diuretics and their doses was prespecified in the protocol and was monitored in both groups. Multivariable regression, ANCOVA, and a generalized linear model were used to fit baseline covariates with furosemide equivalents and changes for 12 months. MEMS-HF participants (n = 239) were grouped in sacubitril/valsartan users [n = 68, 64 ± 11 years, left ventricular ejection fraction (LVEF) 25 ± 9%, cardiac index (CI) 1.89 ± 0.4 L/min/m2] vs. non-users (n = 164, 70 ± 10 years, LVEF 36 ± 16%, CI 2.11 ± 0.58 L/min/m2, P = 0.0002, P < 0.0001, and P = 0.0015, respectively). In contrast, mean pulmonary artery pressure (PAP) values were comparable between groups (29 ± 11 vs. 31 ± 11 mmHg, P = 0.127). Utilization of loop diuretics was lower in patients taking sacubitril/valsartan compared with those without (P = 0.01). Significant predictor of loop diuretic use was a history of renal failure (P = 0.005) but not age (P = 0.091). After subjects were stratified by sacubitril/valsartan or other diuretic use, PAP was nominally, but not significantly lower in sacubitril/valsartan-treated patients (baseline: P = 0.52; 6 months: P = 0.07; 12 months: P = 0.53), while there was no difference in outcome or PAP changes. This difference was observed despite lower CI (P = 0.0015). Comparable changes were not observed for other non-loop diuretics (P = 0.21). Conclusions In patients whose treatment was guided by remote PAP monitoring, concomitant use of sacubitril/valsartan was associated with reduced utilization of loop diuretics, which could potentially be relevant for outcomes

Towards an integrative, eco-evolutionary understanding of ecological novelty: studying and communicating interlinked effects of global change

Global change has complex eco-evolutionary consequences for organisms and ecosystems, but related concepts (e.g., novel ecosystems) do not cover their full range. Here we propose an umbrella concept of “ecological novelty” comprising (1) a site-specific and (2) an organism-centered, eco-evolutionary perspective. Under this umbrella, complementary options for studying and communicating effects of global change on organisms, ecosystems, and landscapes can be included in a toolbox. This allows researchers to address ecological novelty from different perspectives, e.g., by defining it based on (a) categorical or continuous measures, (b) reference conditions related to sites or organisms, and (c) types of human activities. We suggest striving for a descriptive, non-normative usage of the term “ecological novelty” in science. Normative evaluations and decisions about conservation policies or management are important, but require additional societal processes and engagement with multiple stakeholders

A too-many-dwarf-galaxy-satellites problem in the M 83 group

International audienceDwarf galaxies in groups of galaxies provide excellent test cases for models of structure formation. This led to a so-called small-scale crisis, including the famous missing-satellites and too-big-to-fail problems. It was suggested that these two problems can be resolved by introducing baryonic physics to cosmological simulations. We tested the nearby grand spiral M 83 - a Milky Way sibling - to determine whether its number of dwarf galaxy companions is compatible with today's Λ cold dark matter model using two methods: with cosmological simulations that include baryons and with theoretical predictions from the subhalo mass function. By employing distance measurements, we recovered a list of confirmed dwarf galaxies within 330 kpc of M 83 down to a magnitude of MV = −10. We find that both the state-of-the-art hydrodynamical cosmological simulation Illustris-TNG50 and theoretical predictions agree with the number of confirmed satellites around M 83 at the bright end of the luminosity function (> 108 solar masses) but underestimate it at the faint end (down to 106 solar masses) at more than 3σ and 5σ levels, respectively. This indicates a too-many-satellites problem for M 83 in the Λ cold dark matter model. The actual degree of tension with cosmological models is underestimated because the number of observed satellites is incomplete due to the high contamination of spurious stars and Galactic cirrus

The properties of dwarf spheroidal galaxies in the Cen A group: Stellar populations, internal dynamics, and a heart-shaped Halpha ring

Dwarf spheroidal galaxies (dSphs) have been extensively investigated in the Local Group, but their low luminosity and surface brightness make similar work in more distant galaxy groups challenging. Modern instrumentation unlocks the possibility of scrutinizing these faint systems in other environments, expanding the parameter space of group properties. We use MUSE spectroscopy to study the properties of 14 known or suspected dSph satellites of Cen A. Twelve targets are confirmed to be group members based on their radial velocities. Two targets are background galaxies at ∼50 Mpc: KK 198 is a face-on spiral galaxy, and dw1315−45 is an ultra-diffuse galaxy with an effective radius of ∼2300 pc. The 12 confirmed dSph members of the Cen A group have old and metal-poor stellar populations and follow the stellar metallicity-luminosity relation defined by the dwarf galaxies in the Local Group. In the three brightest dwarf galaxies (KK 197, KKs 55, and KKs 58), we identify globular clusters, as well as a planetary nebula in KK 197, although its association with this galaxy and/or the extended halo of Cen A is uncertain. Using four discrete tracers, we measure the velocity dispersion and dynamical mass of KK 197. This dSph appears dark matter dominated and lies on the radial acceleration relation of star-forming galaxies within the uncertainties. It also is consistent with predictions stemming from modified Newtonian dynamics. Surprisingly, in the dwarf KK 203 we find an extended Hα ring. Careful examination of Hubble Space Telescope photometry reveals a very low level of star formation at ages between 30 and 300 Myr. The Hα emission is most likely linked to a ∼40 Myr old supernova remnant, although other possibilities for its origin cannot be entirely ruled out.Key words: galaxies: dwarf / galaxies: kinematics and dynamics / galaxies: stellar content / Galaxy: abundances⋆ The fully reduced data cubes are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/645/A92⋆⋆ Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO program 0101.A-0193(A) and 0101.A-0193(B)

PET-based molecular imaging in neuroscience

Copyright 2003 SPRINGER-VERLAG, New York N

Less loop diuretic use in patients on sacubitril/valsartan undergoing remote pulmonary artery pressure monitoring

Aims Control of pulmonary pressures monitored remotely reduced heart failure hospitalizations mainly by lowering filling pressures through the use of loop diuretics. Sacubitril/valsartan improves heart failure outcomes and increases the kidney sensitivity for diuretics. We explored whether sacubitril/valsartan is associated with less utilization of loop diuretics in patients guided with haemodynamic monitoring in the CardioMEMS European Monitoring Study for Heart Failure (MEMS-HF). Methods and results The MEMS-HF population (n = 239) was separated by the use of sacubitril/valsartan (n = 68) or no use of it (n = 164). Utilization of diuretics and their doses was prespecified in the protocol and was monitored in both groups. Multivariable regression, ANCOVA, and a generalized linear model were used to fit baseline covariates with furosemide equivalents and changes for 12 months. MEMS-HF participants (n = 239) were grouped in sacubitril/valsartan users [n = 68, 64 +/- 11 years, left ventricular ejection fraction (LVEF) 25 +/- 9%, cardiac index (CI) 1.89 +/- 0.4 l/min/m(2)] vs. non users (n = 164, 70 +/- 10 years, LVEF 36 +/- 16%, CI 2.11 +/- 0.58 l/min/m(2), P = 0.0002, P < 0.0001, and P = 0.0015, respectively). In contrast, mean pulmonary artery pressure (PAP) values were comparable between groups (29 +/- 11 vs. 31 +/- 11 mmHg, P = 0.127). Utilization of loop diuretics was lower in patients taking sacubitril/valsartan compared with those without (P = 0.01). Significant predictor of loop diuretic use was a history of renal failure (P = 0.005) but not age (P = 0.091). After subjects were stratified by sacubitril/valsartan or other diuretic use, PAP was nominally, but not significantly lower in sacubitril/valsartan-treated patients (baseline: P = 0.52; 6 months: P = 0.07; 12 months: P = 0.53), while there was no difference in outcome or PAP changes. This difference was observed despite lower CI (P = 0.0015). Comparable changes were not observed for other non-loop diuretics (P = 0.21). Conclusions In patients whose treatment was guided by remote PAP monitoring, concomitant use of sacubitril/valsartan was associated with reduced utilization of loop diuretics, which could potentially be relevant for outcomes