A turn to arts-based research methodology in psychodrama research.

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Stability of power systems and other systems of second order differential equations

Analytic criteria have been developed to predict the stability or instability of equilibrium points of systems of second order differential equations. The results were applied to the swing equations for electric power systems;It was shown that the trivial solution is exponentially stable if and only if the linearization matrix is stable. This rapid rate of convergence ensures that the asymptotic stability of a certain subsystem will imply the stability of the whole system. In the case of uniform damping, stability results proved by linearization allow one to classify equilibrium points as either stable or unstable, except for a certain critical case. To help implement these and related results, an algorithm was developed to determine whether all eigenvalues of a matrix are real and non-positive. Applied to the swing equations with non-trivial transfer conductances, these results demonstrate that an equilibrium solution may not be stable even though (VBAR)(delta)(,i) - (delta)(,j) - (alpha)(,ij)(VBAR) \u3c (pi)/2 for all rotor angle pairs (delta)(,i), (delta)(,j) where (alpha)(,ij) is the complement of the phase of the transfer impedance between machines i and j;Other stability criteria were proved using invariance theory and an extension of the concept of Hamiltonian systems. These results may be applied to the swing equations with negligible transfer conductances. It was shown that equilibrium states for this system may be stable even though most pairs of rotors are more than 90(DEGREES) out of phase; some may be 180(DEGREES) out of phase;A sufficient condition for a non-linear map being one-to-one in a convex region was proved. An application to the swing equations showed that there can be no more than one equilibrium satisfying (VBAR)(delta)(,i) - (delta)(,j) - (alpha)(,ij)(VBAR) \u3c (pi)/2 for all i, j. A simple analytic criterion for the existence of stable equilibrium states was proved for the swing equations with negligible transfer conductances

Products Liability—Conflict Preemption: The United States Supreme Court Denies Preemption Defense for Drug Manufacturers Using FDA-Approved Warning Labels

Wyeth v. Levine, 129 S. Ct. 1187 (2009

A sociometric approach to university teaching—creating group cohesion and a safe learning climate with action methods

The purpose of this article is to explore a sociometric approach to university teaching based on evaluations from students. There are some studies of the application of action methods in university settings focused on teaching skills (see for instance Maya & Maraver, 2020); however, to our knowledge, there are no studies of sociometric approaches to promote group cohesion (GC) and a safe learning climate (SLC) in higher education. To help bridge this knowledge gap, this paper will review the relevant literature and examine evaluations from university students to explore how sociometric techniques may help establish new social connections, and promote self-disclosure, trust, and cohesion. Participants reported that the action methods provided clear structure and frames, which empowered them to stretch their comfort zone but also sparked the formation of numerous new relationships—which some called ‘speed-friendshipping’. Participants experienced increased GC and a feeling of safety regarding future lecture situations. Some participants experienced challenges related to the sociometric exercises, such as too much play and ‘drama activities’. The overall aim of this article is to broaden our understanding of how a sociometric approach may contribute to promote social relationships, GC and facilitate the establishment of an SLC

Tagging of saithe (Pollachius virens L.) at a Norwegian fish farm : preliminary results on migration

Wild fish, particularly saithe (Pollachius virens L.) are commonly observed in the vicinity of fish farm sea cages on the Norwegian west coast and the fish are known to feed on excess salmon food pellets. To investigate residence time at the farm site and subsequent migration pattern, saithe were tagged and released once monthly during the period Nov 1990 to Nov 1991 at the sea cage facility of the Austevoll Marine Research Station, near Bergen, Norway. A total of 2607 saithe were tagged. Preliminary results from tag recoveries show that the saithe can stay in the vicinity of the farm cages for several months before offshore migration to the North Sea, Shetland, Faroe Islands and Iceland

Conditional Standard Error of Measurement: Classical Test Theory, Generalizability Theory and Many-Facet Rasch Measurement with Applications to Writing Assessment

Writing assessments often consist of students responding to multiple prompts, which are judged by more than one rater. To establish the reliability of these assessments, there exist different methods to disentangle variation due to prompts and raters, including classical test theory, Many Facet Rasch Measurement (MFRM), and Generalizability Theory (G-Theory). Each of these methods defines a standard error of measurement (SEM), which is a quantity that summarizes the overall variability of student scores. However, less attention has been given to conditional SEMs (CSEM), which expresses the variability for scores of individual students. This tutorial summarizes how to obtain CSEMs for each of the three methods, illustrates the concepts on real writing assessment data, and provides computational resources for CSEMs including an example of a specification file for the FACETS program for MFRM and R code to compute CSEMs for G-theory

A colloid approach to self-assembling antibodies

Concentrated solutions of monoclonal antibodies have attracted considerable attention due to their importance in pharmaceutical formulations, yet their tendency to aggregate and the resulting high solution viscosity has posed considerable problems. It remains a very difficult task to understand and predict the phase behavior and stability of such solutions. Here we present a systematic study of the concentration dependence of the structural and dynamic properties of monoclonal antibodies using a combination of different scattering methods and microrheological experiments. To interpret these data, we use a colloid-inspired approach based on a simple patchy model, which explicitly takes into account the anisotropic shape and the charge distribution of the molecules. Combining theory, simulations and experiments, we are able to disentangle self-assembly and intermolecular interactions and to quantitatively describe the concentration dependence of structural and dynamic quantities such as the osmotic compressibility, the collective diffusion coefficient and the zero shear viscosity over the entire range of investigated concentrations. This simple patchy model not only allows us to consistently describe the thermodynamic and dynamic behavior of mAb solutions, but also provides a robust estimate of the attraction between their binding sites. It will thus be an ideal starting point for future work on antibody formulations, as it provides a quantitative assessment of the effects of additional excipients or chemical modifications on antibody interactions, and a prediction of their effect on solution viscosity