ABSTRACT
In this study, we analyse the characteristics of stellar populations and the interstellar medium (ISM) in 15 107 early-type central galaxies from the SPIDER survey. Using optical spectra ...from the Sloan Digital Sky Survey (SDSS), we investigate stellar age (Age), metallicity (Z), visual extinction (AV), and H α equivalent width (EWH α) to understand the evolution of the baryonic content in these galaxies. Our analysis explores the relationship between these properties and central velocity dispersion (σ) and halo mass (Mhalo) for isolated centrals (ICs) and group centrals (GCs). Our results confirm that both ICs and GCs’ stellar populations and gas properties are mainly influenced by σ, with Mhalo playing a secondary role. Higher σ values correspond to older, more metal-rich stellar populations in both ICs and GCs. Moreover, fixed σ values we observe younger Ages at higher values of Mhalo, a consistent trend in both ICs and GCs. Furthermore, we investigate the ionization source of the warm gas and propose a scenario where the properties of ionized gas are shaped by a combination of cooling within the intracluster medium (ICM) and feedback from Active Galactic Nuclei (AGNs) assuming a Bondi accretion regime. We observe inherent differences between ICs and GCs, suggesting that the ratio between AGN kinetic power and ICM thermal energy influences EWH α in ICs. Meanwhile, gas deposition in GCs appears to involve a more complex interplay beyond a singular AGN–ICM interaction.
ABSTRACT
The large- and small-scale environments around optically-selected AGN host galaxies and a control sample of non-active galaxies in the MaNGA survey have been investigated in order to ...evaluate the importance of the environment in AGN triggering. Using the MaNGA integral field spectroscopy, we quantify non-circular motions of the ionized gas and detect an excess of radial gas motions in AGN hosts relative to control galaxies, not associated to AGN feedback and are most likely the result of tidal interactions, possibly associated with the triggering of the AGN. We find that the large-scale environments are similar for the AGN hosts and control galaxies in our sample and are biased towards lower large-scale densities and group virial masses, suggestive that the large-scale environment properties is only relevant to the AGN phenomenon in an indirect way, in the form, e.g. of the morphology-density relation. The small-scale environment, as measured by the frequency and luminosity of close neighbours, was also found to be similar for AGN and control galaxies. However, we find a correlation between the intensity of the non-circular gas motions in AGN hosts and the strength of the tidal field, while the control sample does not present such correlation. Also, AGN hosts with the most intense radial gas motions present larger tidal fields than their control galaxies. These findings indicate that at least a fraction of the AGN hosts in our sample have been triggered by tidal interactions with nearby galaxies.
In this study, we analyse the characteristics of stellar populations and the interstellar medium (ISM) in 15,107 early-type central galaxies from the SPIDER survey. Using optical spectra from the ...Sloan Digital Sky Survey (SDSS), we investigate stellar age (Age), metallicity (\(Z\)), visual extinction (\(A_{\rm V}\)), and H\(\alpha\) equivalent width (EWH\(\alpha\)) to understand the evolution of the baryonic content in these galaxies. Our analysis explores the relationship between these properties and central velocity dispersion (\(\sigma\)) and halo mass (\(M_{\rm halo}\)) for isolated centrals (ICs) and group centrals (GCs). Our results confirm that both ICs and GCs' stellar populations and gas properties are mainly influenced by \(\sigma\), with \(M_{\rm halo}\) playing a secondary role. Higher \(\sigma\) values correspond to older, more metal-rich stellar populations in both ICs and GCs. Moreover, fixed \(\sigma\) values we observe younger Ages at higher values of \(M_{\rm halo}\), a consistent trend in both ICs and GCs. Furthermore, we investigate the ionisation source of the warm gas and propose a scenario where the properties of ionised gas are shaped by a combination of cooling within the intra-cluster medium (ICM) and feedback from Active Galactic Nuclei (AGN) assuming a Bondi accretion regime. We observe inherent differences between ICs and GCs, suggesting that the ratio between AGN kinetic power and ICM thermal energy influences EWH\(\alpha\) in ICs. Meanwhile, gas deposition in GCs appears to involve a more complex interplay beyond a singular AGN-ICM interaction.
It has been claimed that high social capital contributes to both positive public health outcomes and to climate change adaptation. Strong social networks have been said to support individuals and ...collective initiatives of adaptation and enhance resilience. As a result, there is an expectation that social capital could reduce vulnerability to risks from the impacts of climate change in the health sector. This paper examines evidence on the role social networks play in individuals’ responses to heat wave risk in a case study in the UK. Based on interviews with independently living elderly people and their primary social contacts in London and Norwich, we suggest that strong bonding networks could potentially exacerbate rather than reduce the vulnerability of elderly people to the effects of heat waves. Most respondents interviewed did not feel that heat waves posed a significant risk to them personally, and most said that they would be able to cope with hot weather. Bonding networks could perpetuate rather than challenge these narratives and therefore contribute to vulnerability rather than ameliorating it. These results suggest a complex rather than uniformly positive relationship between social capital, health and adaptation to climate change.
Genetic introgression with native species is recognized as a detrimental impact resulting from biological invasions involving taxonomically similar invaders. Whilst the underlying genetic mechanisms ...are increasingly understood, the ecological consequences of introgression are relatively less studied, despite their utility for increasing knowledge on how invasion impacts can manifest. Here, the ecological consequences of genetic introgression from an invasive congener were tested using the endemic barbel populations of central Italy, where the invader was the European barbel
Barbus barbus
. Four populations of native
Barbus
species (
B. plebejus
and
B. tyberinus
) were studied: two purebred and two completely introgressed with alien
B. barbus.
Across the four populations, differences in their biological traits (growth, body condition and population demographic structure) and trophic ecology (gut content analysis and stable isotope analysis) were tested. While all populations had similar body condition and were dominated by fish up to 2 years of age, the introgressed fish had substantially greater lengths at the same age, with maximum lengths 410–460 mm in hybrids versus 340–360 mm in native purebred barbel. The population characterized by the highest number of introgressed
B. barbus
alleles (81 %) had the largest trophic niche and a substantially lower trophic position than the other populations through its exploitation of a wider range of resources (e.g. small fishes and plants). These results attest that the genetic introgression of an invasive congener with native species can result in substantial ecological consequences, including the potential for cascading effects.
The purpose of this study is to evaluate the diagnostic performance of MRI parameters to predict adverse maternal peripartum outcomes in pregnant females at high-risk for placenta accreta spectrum ...(PAS) disorder.
This retrospective study evaluated 60 pregnant females who underwent MRI for placental assessment. MRI studies were reviewed by a radiologist blinded to all clinical data. MRI parameters were compared with five maternal outcomes: severe bleeding, cesarean hysterectomy, prolonged operation time, need for blood transfusion, and need for intensive care unit (ICU) admission. The MRI findings were associated with pathologic and/or intraoperative findings for PAS.
The study identified 46 cases of PAS disorder and 16 cases of placenta percreta. The agreement between the radiologist impression of PAS disorder and the intraoperative/histological findings was substantial (0.67,
< 0.001), and almost perfect for the presence of placenta percreta (0.87,
< 0.001). The presence of a placental bulge was highly associated with placenta percreta, with sensitivity of 87.5% and specificity of 90.9%. The MRI signs that associated with more maternal outcomes were myometrial thinning, with significant odds ratio for severe blood loss (20.2), hysterectomy (4.0), need for blood transfusion (4.8) and prolonged surgery time (4.9), and uterine bulging, with significant odds ratio for severe blood loss (11.9), hysterectomy (34.0), ICU admission (5.0), and need for blood transfusion (4.8).
MRI signs significantly correlated with invasive placenta and were independently associated with adverse maternal outcomes. The presence of a placental bulge was highly accurate in predicting placenta percreta.
First study to evaluate the strength of the association between individual MRI signs and five adverse maternal outcomes. Conclusions support published MRI signs associated with placental invasion, especially regarding the value placental bulging in predicting placenta percreta.
Invasions of alien fishes can result in considerable consequences for native biodiversity, including local extinctions of native species through genetic introgression. In Italy, the alien European ...barbel
Barbus barbus
was first detected in 1994. It has since undergone range expansion, raising conservation concerns on their impacts on endemic
Barbus
species, including
Barbus plebejus
and
Barbus tyberinus
. Here, the genetic and phenotypic consequences of
B. barbus
invasion in the Tyrrhenian and Adriatic basins of central Italy were assessed by comparing ‘invaded’ with ‘uninvaded’ river sections that remain free of
B. barbus
due to barriers preventing their upstream dispersal. In both basins, uninvaded sites were confirmed as
B. barbus
free, but the endemic populations had low genetic variability. In the invaded sections, haplotype and nucleotide diversity was relatively high, with introgression skewed towards
B. barbus
genes, with the barbel populations comprising of only 4% and 23% of pure
B. tyberinus
and
B. plebejus
respectively. Relatively high morphological differentiation was apparent between pure
B. tyberinus
and hybrid forms, whilst differences were less apparent between pure
B. plebejus
and their hybrid forms. Thus, the endemic
Barbus
species only persist in areas that remain free of invasive
B. barbus
, with this only due to river structures that impede their upstream movements. As these structures also limit the effective population size of the endemic species, conservation plans must reconcile
B. barbus
dispersal prevention with the need to increase the population connectivity of the endemics.
Background Most projections of climate change suggest an increased frequency of heatwaves in England over coming decades; older people are at particular risk. This could result in substantial ...mortality and morbidity. Objective To determine elderly people's knowledge and perceptions of heat-related risks to health, and of protective behaviours. Methods Semi-structured interviews: 73 men and women, 72–94 years, living in their own homes in London and Norwich, UK. Results Few respondents considered themselves either old or at risk from the effects of heat, even though many had some form of relevant chronic illness; they did recognize that some medical conditions might increase risks in others. Most reported that they had taken appropriate steps to reduce the effects of heat. Some respondents considered it appropriate for the government to take responsibility for protecting vulnerable people, but many thought state intervention was unnecessary, intrusive and unlikely to be effective. Respondents were more positive about the value of appropriately disseminated advice and solutions by communities themselves. Conclusion The Heatwave Plan should consider giving greater emphasis to a population-based information strategy, using innovative information dissemination methods to increase awareness of vulnerability to heat among the elderly and to ensure clarity about behaviour modification measures.
Exposure to environmental stressors during pregnancy plays an important role in influencing subsequent susceptibility to certain chronic diseases through the modulation of epigenetic mechanisms, ...including DNA methylation. Our aim was to explore the connections between environmental exposures during gestation with DNA methylation of placental cells, maternal and neonatal buccal cells by applying artificial neural networks (ANNs). A total of 28 mother-infant pairs were enrolled. Data on gestational exposure to adverse environmental factors and on mother health status were collected through the administration of a questionnaire. DNA methylation analyses at both gene-specific and global level were analyzed in placentas, maternal and neonatal buccal cells. In the placenta, the concentrations of various metals and dioxins were also analyzed. Analysis of ANNs revealed that suboptimal birth weight is associated with placental
methylation, maternal stress during pregnancy with methylation levels of
and
in placentas and mother's buccal DNA, respectively, and exposure to air pollutants with maternal
methylation. Associations were also observed between placental concentrations of lead, chromium, cadmium and mercury with methylation levels of
in placentas,
in maternal buccal cells and placentas,
in neonatal buccal cells, and
in maternal buccal cells. Furthermore, dioxin concentrations were associated with placental
, neonatal
and maternal
gene methylation levels. Current results suggest that exposure of pregnant women to environmental stressors during pregnancy could induce aberrant methylation levels in genes linked to several pathways important for embryogenesis in both the placenta, potentially affecting foetal development, and in the peripheral tissues of mothers and infants, potentially providing peripheral biomarkers of environmental exposure.
Two fluviolacustrine lineages (SI1 Barbus and SI2 Barbus) of the Barbus genus have been recently detected in the Apulia‐Campania ichthyogeographic district (southern Italy). The aim of this study was ...to determine the taxonomic status of these lineages by comparing them with the two already‐established Italian fluviolacustrine species Barbus plebejus and Barbus tyberinus through a more in‐depth molecular and morphological investigation. Genetic analyses were performed on both mitochondrial (cytochrome b) and nuclear (growth hormone paralog 2) DNA markers, and morphological analyses were carried out on specific age classes and purebred populations. Molecular analyses detected four evolutionary lineages at the mitochondrial level, whereas the nuclear data set highlighted the strict evolutionary relation between B. plebejus sensu stricto and the new lineages, converged in the B. plebejus complex clade. The morphological analyses allowed us to discriminate SI1 Barbus and SI2 Barbus from both B. plebejus and B. tyberinus. The new taxa could be discriminated by the greatest maximum body height and the longest pre‐orbital distance, respectively. Both the new lineages have longer ventral and pectoral fins than B. plebejus and B. tyberinus, a larger caudal fin than B. tyberinus and a lower number of scales along the lateral line than B. plebejus. Both molecular and morphological results suggested the two southern Italian lineages could be considered as distinct endemic species: the formal description of the new species Barbus samniticus sp. nov. (i.e., SI1 Barbus) and the revalidation of Barbus fucini Costa, 1853 (i.e., SI2 Barbus) were thus proposed, and, for both species, molecular and morphological diagnosis were provided.
PDF
