A pitfall of piecewise-polytropic equation of state inference

The only messenger radiation in the Universe which one can use to statistically probe the Equation of State (EOS) of cold dense matter is that originating from the near-field vicinities of compact stars. Constraining gravitational masses and equatorial radii of rotating compact stars is a major goal for current and future telescope missions, with a primary purpose of constraining the EOS. From a Bayesian perspective it is necessary to carefully discuss prior definition; in this context a complicating issue is that in practice there exist pathologies in the general relativistic mapping between spaces of local (interior source matter) and global (exterior spacetime) parameters. In a companion paper, these issues were raised on a theoretical basis. In this study we reproduce a probability transformation procedure from the literature in order to map a joint posterior distribution of Schwarzschild gravitational masses and radii into a joint posterior distribution of EOS parameters. We demonstrate computationally that EOS parameter inferences are sensitive to the choice to define a prior on a joint space of these masses and radii, instead of on a joint space interior source matter parameters. We focus on the piecewise-polytropic EOS model, which is currently standard in the field of astrophysical dense matter study. We discuss the implications of this issue for the field.Comment: 16 pages, 9 figures. Accepted for publication in MNRA

On parametrised cold dense matter equation of state inference

Constraining the equation of state of cold dense matter in compact stars is a major science goal for observing programmes being conducted using X-ray, radio, and gravitational wave telescopes. We discuss Bayesian hierarchical inference of parametrised dense matter equations of state. In particular we generalise and examine two inference paradigms from the literature: (i) direct posterior equation of state parameter estimation, conditioned on observations of a set of rotating compact stars; and (ii) indirect parameter estimation, via transformation of an intermediary joint posterior distribution of exterior spacetime parameters (such as gravitational masses and coordinate equatorial radii). We conclude that the former paradigm is not only tractable for large-scale analyses, but is principled and flexible from a Bayesian perspective whilst the latter paradigm is not. The thematic problem of Bayesian prior definition emerges as the crux of the difference between these paradigms. The second paradigm should in general only be considered as an ill-defined approach to the problem of utilising archival posterior constraints on exterior spacetime parameters; we advocate for an alternative approach whereby such information is repurposed as an approximative likelihood function. We also discuss why conditioning on a piecewise-polytropic equation of state model - currently standard in the field of dense matter study - can easily violate conditions required for transformation of a probability density distribution between spaces of exterior (spacetime) and interior (source matter) parameters.Comment: Accepted for publication in MNRAS, 43 pages, 7 figure

Effect of plant domestication on the rhizosphere microbiome of common bean (Phaseolus vulgaris) .

Plant domestication was a pivotal achievement for human civilization and subsequent plant improvement increased crop productivity and quality. However, domestication also caused a strong reduction in the genetic diversity of modern cultivars compared to their wild relatives. It is known that plants rely, in part, on the rhizosphere microbial community for wreowth, development and tolerance to (a)biotic stresses. Hence, plant domestication events may have adversely affected the bacterial diversity of the rhizosphere of two wild relatives, three landraces and three modern cultivars of common bean (Phaseolus vulgaris). These different lines belong to the Mesoamerican bean gene pool of Colombia and were selected amongst more than 37,000 accessions kept in the Genetic Resources Program of the International Centre for Tropical Agriculture (CIAT, Colombia). The eight accessions were grown in both native and in agricultural soils collected in the province of Antioquia (Colombia). At different plant growth stages, DNA was extracted from rhizospheric soil and bacterial taxonomic diversity was analysed by metagenomic sequencing of the V3-V4 region of the 16S rRNA. Our Approach of going ?back to the roots? using native soils togheter with wild relatives provides new fundamental insights in host genotype-mediated recruitment of beneficial microbes and in the functional and metabolic potential of the rhizosphere microbiome of native soils and wild relatives of modern crop cultivars

Psychometric properties of the Screen for Child Anxiety Related EmotionalDisorders (SCARED) in the general Italian adolescent population:A validation and a comparison between Italy and The Netherlands

In this study examination is given to the psychometric properties of the Italian version of the Screen for Child Anxiety Related Emotional Disorders (SCARED) in a large community sample of adolescents. Additionally, a comparison was made between the anxiety scores of this Italian adolescent cohort (N = 1975) and a comparative Dutch adolescent cohort (N = 1115). Findings revealed that a five-factor structure of the SCARED applied not only to the Italian adolescents from the general community, but also to boys and girls, and to early and middle adolescents. Moreover, sex and age differences on anxiety scores within the Italian sample were found to be consistent with previous studies of adolescent anxiety disorders. Finally, Italian adolescents reported higher anxiety scores than their Dutch peers. Findings of this study highlight that the SCARED is a valid screening instrument to rate anxiety symptoms of Italian adolescents

Temperatuuronderzoek bij tomaat :effect van een tijdelijke temperatuurverlaging (DROP) op groei, ontwikkeling en productie

Om na te gaan op welk moment van de dag de plant het meest gevoelig is voor temperatuur is een experiment uitgevoerd in klimaatkamers. Om na te gaan wat het effect is van een tijdelijke temperatuurverlaging na zonsopkomst op groei en productie van tomaten is een kasexperiment uitgevoerd.Voor de praktijk betekenen de resultaten dat een temperatuurdaling bij jonge planten beter niet toegepast kan worden, omdat dit ten koste gaat van de opbouw van het bladoppervlak en daarmee ook van de groei. Bij planten met voldoende bladoppervlak heeft een temperatuurdaling in de ochtend geen negatieve effecten op gewasgroei en producti

A Parametric Study of Radiative Dipole Body Array Coil for 7 Tesla MRI

In this contribution we present numerical and experimental results of a parametric quantitative study of radiative dipole antennas in a phased array configuration for efficient body magnetic resonance imaging at 7T via parallel transmission. For magnetic resonance imaging (MRI) at ultrahigh fields (7T and higher) dipole antennas are commonly used in phased arrays, particularly for body imaging targets. This study reveals the effects of dipole positioning in the array (elevation of dipoles above the subject and inter-dipole spacing) on their mutual coupling, $B_1^{+}$ per $P_{acc}$ and $B_1^{+}$ per maximum local SAR efficiencies as well as the RF-shimming capability. The numerical and experimental results are obtained and compared for a homogeneous phantom as well as for a real human models confirmed by in-vivo experiments

Data protection, safeguarding and the protection of children's privacy: exploring local authority guidance on parental photography at school events

Should parents be allowed to take photographs at school events? Media reports suggest that increasingly schools are answering no to this question, either prohibiting or imposing stringent restrictions upon such photography. The legal justifications for such restrictions are, however, unclear. Accordingly, in 2013 freedom of information requests were sent to local education authorities across England, Scotland and Wales, the aim being to determine what advice local education authorities provide to schools in relation to parental photography at school events, and to identify how education authorities’ understandings of the law influence the advice they offer. That research reveals that local education authorities’ understandings of the law vary significantly and that where authorities do not fully appreciate the extent of the legal obligations arising this may have significant repercussions for the children concerned

Temperature calibration procedure for thin film substrates for thermo-ellipsometric analysis using melting point standards

Precise and accurate temperature control is pertinent to studying thermally activated processes in thin films. Here, we present a calibration method for the substrate–film interface temperature using spectroscopic ellipsometry. The method is adapted from temperature calibration methods that are well developed for thermogravimetric analysis and differential scanning calorimetry instruments, and is based on probing a transition temperature. Indium, lead, and zinc could be spread on a substrate, and the phase transition of these metals could be detected by a change in the C signal of the ellipsometer. For water, the phase transition could be detected by a loss of signal intensity as a result of light scattering by the ice crystals. The combined approach allowed for construction of a linear calibration curve with an accuracy of 1.3 C or lower over the full temperature range