Pulling out threads from the cosmic tapestry: Defining filaments of galaxies

Filaments of galaxies are the dominant feature of modern large-scale redshift surveys. They can account for up to perhaps half of the baryonic mass budget of the Universe and their distribution and abundance can help constrain cosmological models. However, there remains no single, definitive way in which to detect, describe, and define what filaments are and their extent. This work examines a number of physically motivated, as well as statistical, methods that can be used to define filaments and examines their relative merits.

Defining worthwhile and desired responses to treatment of chronic low back pain

Objective To describe patients' perceptions of minimum worthwhile and desired reductions in pain and disability upon commencing treatment for chronic low back pain. Design and Setting Descriptive study nested within a community-based randomized controlled trial on prolotherapy injections and exercises. Patients A total of 110 participants with chronic low back pain. Interventions Prior to treatment, participants were asked what minimum percentage reductions in pain and disability would make treatment worthwhile and what percentage reductions in pain and disability they desired with treatment. Outcome Measures. Minimum worthwhile reductions and desired reductions in pain and disability. Results. Median (inter-quartile range) minimum worthwhile reductions were 25% (20%, 50%) for pain and 35% (20%, 50%) for disability. This compared with desired reductions of 80% (60%, 100%) for pain and 80% (50%, 100%) for disability. The internal consistency between pain and disability responses was high (Spearman's coefficient of association of 0.81 and 0.87, respectively). A significant association existed between minimum worthwhile reductions and desired reductions, but no association was found between these two factors and patient age, gender, pain severity or duration, disability, anxiety, depression, response to treatment, or treatment satisfaction. Conclusions. Inquiring directly about patients' expectations of reductions in pain and in disability is important in establishing realistic treatment goals and setting benchmarks for success. There is a wide disparity between the reductions that they regard as minimum worthwhile and reductions that they hope to achieve. However, there is a high internal consistency between reductions in pain and disability that they expect.

A flaw in the use of minimal defining sets for secret sharing schemes

It is shown that in some cases it is possible to reconstruct a block design D uniquely from incomplete knowledge of a minimal defining set for D. This surprising result has implications for the use of minimal defining sets in secret sharing schemes.

Modern Drama: Defining the Field

Theatre, like other subjects in the humanities, has recently undergone quintessential changes in theory, approach, and research. Modern Drama - a collection of twelve essays from leading theatre and drama scholars - investigates the contemporary meanings and the cultural and political resonances of the terms inherent in the concepts of 'modern' and 'drama, ' delving into a range of theoretical questions on the history of modernism, modernity, post-modernism, and postmodernity as they have intersected with the shifting histories of drama, theatre, and performance.

A formal object-oriented approach to defining consistency constraints for UML models

We discuss how integrity consistency constraints between different UML models can be precisely defined at a language level. In doing so, we introduce a formal object-oriented metamodeling approach. In the approach, integrity consistency constraints between UML models are defined in terms of invariants of the UML model elements used to define the models at the language-level. Adopting a formal approach, constraints are formally defined using Object-Z. We demonstrate how integrity consistency constraints for UML models can be precisely defined at the language-level and once completed, the formal description of the consistency constraints will be a precise reference of checking consistency of UML models as well as for tool development.