Decomposition tables for experiments. II. Two--one randomizations

We investigate structure for pairs of randomizations that do not follow each other in a chain. These are unrandomized-inclusive, independent, coincident or double randomizations. This involves taking several structures that satisfy particular relations and combining them to form the appropriate orthogonal decomposition of the data space for the experiment. We show how to establish the decomposition table giving the sources of variation, their relationships and their degrees of freedom, so that competing designs can be evaluated. This leads to recommendations for when the different types of multiple randomization should be used.Comment: Published in at http://dx.doi.org/10.1214/09-AOS785 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Decomposition tables for experiments I. A chain of randomizations

One aspect of evaluating the design for an experiment is the discovery of the relationships between subspaces of the data space. Initially we establish the notation and methods for evaluating an experiment with a single randomization. Starting with two structures, or orthogonal decompositions of the data space, we describe how to combine them to form the overall decomposition for a single-randomization experiment that is ``structure balanced.'' The relationships between the two structures are characterized using efficiency factors. The decomposition is encapsulated in a decomposition table. Then, for experiments that involve multiple randomizations forming a chain, we take several structures that pairwise are structure balanced and combine them to establish the form of the orthogonal decomposition for the experiment. In particular, it is proven that the properties of the design for such an experiment are derived in a straightforward manner from those of the individual designs. We show how to formulate an extended decomposition table giving the sources of variation, their relationships and their degrees of freedom, so that competing designs can be evaluated.Comment: Published in at http://dx.doi.org/10.1214/09-AOS717 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Cauchy horizon stability in self-similar collapse: scalar radiation

The stability of the Cauchy horizon in spherically symmetric self-similar collapse is studied by determining the flux of scalar radiation impinging on the horizon. This flux is found to be finite.Comment: 10 pages. To appear in Phys Rev

Patient Motivational Language as a Predictor of Symptom Change, Hazard of Clinically Significant Response, and Time to Response in Psychotherapy for Generalized Anxiety Disorder

Change-talk (CT), or self-arguments for change, has been associated with favorable patient outcomes, while counter change-talk (CCT), or self-arguments against change, has been associated with poorer outcomes. Most studies on change language have focused on the prediction of distal posttreatment outcomes, while the prediction of more proximal outcomes has remained largely untested. Addressing this gap, we examined early treatment CT and CCT as predictors of worry change trajectories, “hazard” of clinically significant response, and time to response (i.e., outcome efficiency) in CBT and CBT integrated with MI (MI-CBT) for generalized anxiety disorder (GAD). We also explored whether treatment type moderated these associations. Data derived from a randomized controlled trial comparing CBT (n = 43) and MI-CBT (n = 42) for GAD. Independent observers reliably coded CT/CCT during session 1. Patients rated their worry after every session. Multilevel modeling revealed that, across both treatments, more CT associated with lower midtreatment worry level (p = .03), whereas more CCT associated with a slower rate of worry reduction at midtreatment (p = .04). However, treatment moderated the associations between CT and both midtreatment worry level (p = .004) and rate of change (p = .03). In CBT, patients with higher vs. lower CT had less worry and a faster rate of worry reduction; in MI-CBT, CT was unrelated to midtreatment worry level and the rate of worry change. Treatment did not moderate the CCT-worry relations. Survival analyses revealed that, across both treatments, more CT associated with a greater hazard of response (p = .004) and approached a faster time to response (p = .05), and more CCT associated with a lower hazard of response (p = .002) and approached a slower time to response (p = .06). Patient motivational language predicts proximal outcomes, and may be useful in differential treatment selection

Investigation of relationships between linears, tonal and hazy anomalies, and petroleum production in the Williston Basin: An ERTS approach

There are no author-identified significant results in this report

Cell proliferation and differentiation kinetics during spermatogenesis in Hydra carnea

Spermatogenesis inHydra carnea was investigated. The cell proliferation and differentiation kinetics of intermediates in the spermatogenesis pathway were determined, using quantitative determinations of cell abundance, pulse and continuous labelling with3H-thymidine and nuclear DNA measurements. Testes develop in the ectoderm of male hydra as a result of interstitial cell proliferation. Gonial stem cells and proliferating spermatogonia have cell cycles of 28 h and 22 h, respectively. Stem cells undergo four, five or six cell divisions prior to meiosis which includes a premeiotic S+G2 phase of 20 h followed by a long meiotic prophase (22 h). Spermatid differentiation requires 12–29 h. When they first appear, testes contain only proliferating spermatogonia; meiotic and postmeiotic cells appear after 2 and 3 days, respectively and release of mature sperm begins after 4 days. Mature testes produce about 27,000 sperm per day over a period of 4–6 days: about 220 gonial stem cells per testis are required to support this level of sperm differentiation. Further results indicate that somatic (e.g. nematocyte) differentiation does not occur in testes although it continues normally in ectodermal tissue outside testes. Our results support the hypothesis that spermatogenesis is controlled locally in regions of the ectoderm where testes develop

The dialogic city: towards a synthesis of physical and conceptual artefacts in urban community configurations

This paper addresses a question in urban research relating to definitions of the physical and conceptual artefacts that comprise local urban communities. These artefacts are, we suggest, products of complex relationships between discursive and non -discursive agencies in urban contexts. We focus on the problems of defining conceptual artefacts by considering how urban communities’ social meanings are embedded in their spatial configurations, conceptualizations and practices. Considering the relational nature of the built environment, we describe the interplays of space, society and meaning as being ‘dialogic’. By this we mean that the urban environment’s discursive and non-discursive agencies inform and transform each other through processes of their complex inter-dependencies. These dialogic processes also occur where professional and community practitioners seek to transform the built environment by exchanging their conceptualizations and definitions. Towards a refocusing upon conceptual artefacts in the built environment, we review a selection of diverse research from the fields of space syntax, actor -network theory in architecture, and urban sociologies of crime and deprivation. We sample from specific studies of urban spatial effects upon local community behaviours. We observe that processes of conceptualization are revealed in professionals’ definitions of urban environments. Moreover, we draw attention to the lack of community -membership definitions in many urban interventions. We argue that this lack persists because community conceptualizations, based upon ‘mental models’, tend to be reflected in quotidian or sub -conscious practices, which do not enter the standard professional discourse. We reflect critically on the urban research studies sampled, considering in particular their treatment of the role of conceptualizations in shaping the urban environment. Building on this critique, we argue that the notion of ‘mental models’ is overlooked in the urban research literature and warrants further investigation. Working towards a synthesis of physical and conceptual artefacts, we attempt an outline of the significance of inter -dependencies in urban formations. Hence we consider the role played by local conceptualizations in phenomena such as neighbourhood boundaries, community foci, stereotypes of others and place -specific community values. Finally, we outline the requirements for a method to examine these conceptualizations

Concerns with AED conversion: comparison of patient and physician perspectives.

When discussing AED conversion in the clinic, both the patient and physician perspectives on the goals and risks of this change are important to consider. To identify patient-reported and clinician-perceived concerns, a panel of epilepsy specialists was questioned about the topics discussed with patients and the clinician's perspective of patient concerns. Findings of a literature review of articles that report patient-expressed concerns regarding their epilepsy and treatment were also reviewed. Results showed that the specialist panel appropriately identified patient-reported concerns of driving ability, medication cost, seizure control, and medication side effects. Additionally, patient-reported concerns of independence, employment issues, social stigma, medication dependence, and undesirable cognitive effects are important to address when considering and initiating AED conversion