Menus for Feeding Black Holes

Black holes are the ultimate prisons of the Universe, regions of spacetime where the enormous gravity prohibits matter or even light to escape to infinity. Yet, matter falling toward the black holes may shine spectacularly, generating the strongest source of radiation. These sources provide us with astrophysical laboratories of extreme physical conditions that cannot be realized on Earth. This chapter offers a review of the basic menus for feeding matter onto black holes and discusses their observational implications.Comment: 27 pages. Accepted for publication in Space Science Reviews. Also to appear in hard cover in the Space Sciences Series of ISSI "The Physics of Accretion onto Black Holes" (Springer Publisher

Confirmation of triple shape coexistence in 179Hg: Focal plane spectroscopy of the α decay of 183Pb

The α decay of 183Pb has been studied in detail at the focal plane of the RITU gas-filled separator. The four previously known α decay branches have been ordered into the decay of two isomers in 183Pb. The deduced decay scheme and the interpretation of the inferred α decay hindrance factors and γ rays observed at the focal plane are strongly in favor of the recent suggestion of triple shape coexistence-oblate, prolate, and near-spherical in the daughter nucleus 179Hg

The genetic architecture of the human cerebral cortex

INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 306 nominally genome-wide significant loci (P < 5 × 10−8) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 299 loci for which replication data were available, 241 loci influencing surface area and 14 influencing thickness remained significant after replication, with 199 loci passing multiple testing correction (P < 8.3 × 10−10; 187 influencing surface area and 12 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation (rG = −0.32, SE = 0.05, P = 6.5 × 10−12), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 10 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Identifying Sources of Faecal Contamination in a Small Urban Stream Catchment: A Multiparametric Approach

Small urban streams discharging in the proximity of bathing waters may significantly contribute to the deterioration of water quality, yet their impact may be overlooked. This study focuses on the Elm Park stream in the city of Dublin that is subject to faecal contamination by unidentified sources. The aim of the study was to identify a minimum number of “sentinel” sampling stations in an urban catchment that would provide the maximum amount of information regarding faecal pollution in the catchment. Thus, high-resolution sampling within the catchment was carried out over the course of 1 year at 11 stations. Faecal indicator bacteria were enumerated and microbial source tracking (MST) was employed to evaluate human pollution. In addition, ammonium, total oxidised nitrogen, and phosphorus levels were monitored to determine if these correlated with faecal indicator and the HF183 MST marker. In addition, the effect of severe weather events on water quality was assessed using automated sampling at one of the identified “sentinel” stations during baseflow and high flow conditions over a 24-h period. Our results show that this urban stream is at times highly contaminated by point source faecal pollution and that human faecal pollution is pervasive in the catchment. Correlations between ammonium concentrations and faecal indicator bacteria (FIB) as well as the human MST marker were observed during the study. Cluster analysis identified four “sentinel” stations that provide sufficient information on faecal pollution in the stream, thus reducing the geographical complexity of the catchment. Furthermore, ammonium levels strongly correlated with FIB and the human HF183 MST marker under high flow conditions at key “sentinel” stations. This work demonstrates the effectiveness of pairing MST, faecal indicators, and ammonium monitoring to identify “sentinel” stations that could be more rapidly assessed using real-time ammonium readouts to assess remediation efforts.</p

Enhancing the social dimension of development: Interconnecting the Capability Approach and applied knowledge of social workers

The current interest in sustainability within international development presents an important opportunity for social work to further promote the often-overlooked social pillar of sustainable development. The dominant paradigm regarding economic systems of development and organisation has influenced not only the scope of sustainable development, but also an increasingly depoliticised vision of social work knowledge and practice. Inattention to structural determinants of social inequalities limits the scope for radical, sustained change. The Capability Approach’s recognition of poverty and development as complex, multidimensional phenomena aligns with social work values, while social work’s well-established and reflexive direct-level practice may provide the applied knowledge needed in the theory

Building Theoretical Foundations for Electronic Governance Benchmarking

Part 1: FoundationsInternational audienceThe success of the electronic governance (EGOV) benchmarking has been limited so far. Lacking a theory to integrate existing conceptualizations has made the acquisition and sharing of knowledge produced by different benchmarking exercises difficult. In order to address this problem, this paper: 1) explains the nature of the EGOV benchmarking activity though a wellestablished theoretical framework - Activity Theory, 2) applies the framework to carry out a mapping between a number of existing EGOV benchmarking conceptualizations, 3) develops an unified conceptualization based on these mappings and 4) validates the resulting model though a real-life national EGOV strategy development project. The use of the Activity Theory in the paper has enabled defining and relating initial dimensions of the EGOV benchmarking activity, and mapping the dimensions present in existing conceptualizations. This not only created a unifying theoretical basis for conceptualizing the EGOV benchmarking activity but allowed learning from and integrating existing conceptualizations. The work impacts on the EGOV benchmarking practice by enabling a logical design of the activity, and contextually correct understanding of existing EGOV benchmarking results with respect to their intended usage

Building Theoretical Foundations for Electronic Governance Benchmarking

The success of the electronic governance (EGOV) benchmarking has been limited so far. Lacking a theory to integrate existing conceptualizations has made the acquisition and sharing of knowledge produced by different benchmarking exercises difficult. In order to address this problem, this paper: 1) explains the nature of the EGOV benchmarking activity though a well-established theoretical framework - Activity Theory, 2) applies the framework to carry out a mapping between a number of existing EGOV benchmarking conceptualizations, 3) develops an unified conceptualization based on these mappings and 4) validates the resulting model though a real-life national EGOV strategy development project. The use of the Activity Theory in the paper has enabled defining and relating initial dimensions of the EGOV benchmarking activity, and mapping the dimensions present in existing conceptualizations. This not only created a unifying theoretical basis for conceptualizing the EGOV benchmarking activity but allowed learning from and integrating existing conceptualizations. The work impacts on the EGOV benchmarking practice by enabling a logical design of the activity, and contextually correct understanding of existing EGOV benchmarking results with respect to their intended usage

Anomalous Coulomb matrix elements in the f7/2 shell

γ decays from high-spin states in the N=Z-1 nucleus 2753Co26 have been identified for the first time. Level energies and Coulomb energy differences between these states and their analogs in its mirror nucleus 53Fe have been compared with large-scale pf shell-model calculations, which offer excellent agreement. New information has been obtained on two-proton Coulomb matrix elements needed in the interpretation. These have been extracted from the data via a number of methods and are shown to exhibit an anomalous behavior for the J=2 coupling