Verbena officinalis Verbenaceae (Lamiales): a new plant model system for phyllotaxis research

Phyllotactic diversity and developmental transitions between phyllotactic patterns are not fully understood. The plants studied so far, such as Magnolia, Torreya or Abies, are not suitable for experimental work, and the most popular model plant, Arabidopsis thaliana, does not show sufficient phyllotactic variability. It has been found that in common verbena (Verbena officinalis L.), a perennial, cosmopolitan plant, phyllotaxis differs not only between growth phases in primary transitions but also along the indeterminate inflorescence axis in a series of multiple secondary transitions. The latter are no longer associated with the change in lateral organ identity, and the sequence of phyllotactic patterns is puzzling from a theoretical point of view. Data from the experiments in silico, confronted with empirical observations, suggest that secondary transitions might be triggered by the cumulative effect of fluctuations in the continuously decreasing bract primordia size. The most important finding is that the changes in the primary vascular system, associated with phyllotactic transitions, precede those taking place at the apical meristem. This raises the question of the role of the vascular system in determining primordia initiation sites, and possibly challenges the autonomy of the apex. The results of this study highlight the complex relationships between various systems that have to coordinate their growth and differentiation in the developing plant shoot. Common verbena emerges from this research as a plant that may become a new model suitable for further studies on the causes of phyllotactic transitions.

The Relationship Between Teachers’ Inclusion-Related Knowledge, Skills, and Attitudes and Student Outcomes: A Review of Recent Literature

In this article, we report on a scoping review of empirical literature addressing the relationship between teachers’ inclusion-related knowledge, skills, and attitudes and student outcomes. Using six common electronic databases for education (ProQuest, JSTOR, SAGE Journals Online, ScienceDirect, PsycINFO, PsycARTICLES), we searched for peer-reviewed, English-language publications between 1 January 2008 and 1 January 2018 (a 10-year period). A total of 25 articles met the search criteria for this scoping review and were consequently subject to a more detailed examination. This more detailed examination focused upon five student variables (intellectual disabilities [IDs], learning disabilities [LDs], autism spectrum disorder [ASD], other mental health disorders, and giftedness) and five possible student outcomes (social well-being, functional or life skills, academic achievement, post-secondary transitions, and exceptionality-related outcomes). These 25 articles include eight systematic or scoping reviews, two that report on experimental studies, nine that report on quasi-experimental studies, and six that report on correlational-descriptive research studies. A summary account of these 25 articles is offered, as is a list of related implications, for both practice and inquiry. Some of the most significant implications are related to the limited body of evidence related to a number of variables; these include teachers’ attitudes and resultant student outcomes, giftedness, and post-secondary transitions. Additionally, these implications also offer cautionary considerations related to teachers delivering mental health-related programs and utilizing technology-related interventions for students with ASD.

The non-linear relationship between parental wealth and children’s post- secondary transitions in Germany

Our paper addresses the relationship between parental wealth and children’s post-secondary transitions. More specifically, we contrast the likelihood of children with an upper secondary degree to make a transition into further education or the labor market with their likelihood to stay inactive, i.e., to engage neither in further education nor in labor market activity (NEET) after leaving school for the first time. While previous research argues that there is a general positive association between parental wealth and children’s educational and occupational transitions, we argue that for children of wealthy parents, this association might be weaker or even negative. Our study focuses on Germany, where wealth has a weak correlation with the traditional measures of parental socio-economic background. For our empirical analyses, we apply data from the German Socio-Economic Panel Study (SOEP) and use binary logistic regression models for discrete-time event history analyses. Although not statistically significant, our results show that the relationship between parental wealth and children’s post-secondary transitions is not linear. Our study contributes to previous research by providing a detailed examination of the potential mechanisms underlying the relationship between parental wealth and children’s post-secondary transitions.

A simple angle integration method for the determination of capture reaction cross sections

In order to determine the cross section of a reaction by the angular distribution method, it is essential to calculate the angular distributions of all secondary transitions that lead to the ground state. This is achieved by analysing spectra from HPGe detectors at various detection angles, which is a time consuming process. In this work, a simpler angle integration method is presented that allows to determine cross sections of capture reactions by measuring spectra at fewer detection angles.

Continuation and stability of rotating waves in the magnetized spherical Couette system: secondary transitions and multistability

Rotating waves (RW) bifurcating from the axisymmetric basic magnetized spherical Couette (MSC) flow are computed by means of Newton–Krylov continuation techniques for periodic orbits. In addition, their stability is analysed in the framework of Floquet theory. The inner sphere rotates while the outer is kept at rest and the fluid is subjected to an axial magnetic field. For a moderate Reynolds number Re = 10 3 (measuring inner rotation), the effect of increasing the magnetic field strength (measured by the Hartmann number Ha ) is addressed in the range Ha ∈(0, 80) corresponding to the working conditions of the HEDGEHOG experiment at Helmholtz-Zentrum Dresden-Rossendorf. The study reveals several regions of multistability of waves with azimuthal wavenumber m = 2, 3, 4, and several transitions to quasi-periodic flows, i.e modulated rotating waves. These nonlinear flows can be classified as the three different instabilities of the radial jet, the return flow and the shear layer, as found in the previous studies. These two flows are continuously linked, and part of the same branch, as the magnetic forcing is increased. Midway between the two instabilities, at a certain critical Ha , the non-axisymmetric component of the flow is maximum.