Acceleration Of Protons To Above 6 MeV Using H2O >Snow> Nanowire Targets

A scheme is presented for using H2O >snow> nanowire targets for the generation of fast protons. This novel method may relax the requirements for very high laser intensities, thus reducing the size and cost of laser based ion acceleration system.Physic

Cognition as Context (Whose Cognition?)

This is an electronic version of an article published in POTTER, J., 1998. Cognition as context (whose cognition?). Research on Language and Social Interaction, 31 pp. 29 - 44. Research on Language and Social Interaction is available online at: http://www.tandfonline.com/doi/abs/10.1207/s15327973rlsi3101_2In a series of papers Emanuel Schegloff (1987, 1989, 1991, 1992a, b, 1997) has developed arguments concerning the coherence of analytic procedures for addressing entities that would traditionally have been glossed as ‘social structure’ or ‘social context’. He argues that ‘social context’ should be treated as relevant to analysis only insofar as it features as a participants’ concern; that is, only insofar as it is invoked, formulated, oriented to, or displayed in actual interaction. Research conclusions should be disciplined by attending to the procedural consequentiality of any claimed contextual particular. This paper will briefly review Schegloff’s argument and pick out some themes that have been highlighted by recent work in discursive psychology (Edwards and Potter, 1992, 1993; Edwards, 1997; Potter, 1996). In particular, it will emphasise the way that cognition, in some form or other, is often treated as a taken-for-granted background in discussions of context. In effect, cognition is treated as the inner stuff of perception, storage and inferences and it is set over against an outer reality of context, which might be events, settings and social structures. However, that reality is typically seen as having its effect via its cognitive perception, representations and processing. The paper will argue that cognition can be subject to some of the same analytic moves as context and that, indeed, in participants’ discourse things that analysts have traditionally glossed under the categories ‘cognition’ and ‘context’ often blur together. My suggestion is that ‘cognition’ and ‘reality’, conventionally the inner and the outer, can be treated in the same way as things which are formulated, attended to, and oriented to in discourse. In this way cognition becomes a topic of discursive study, but is respecified in the process. In the title of a recent paper, Schegloff (1997) asks the rhetorical question Whose Context? This highlights the questionable status of analysts versions of context vis a vis 3 those of participants. My subtitle – Whose Cognition? – raises a parallel question with respect to cognition

Interactional positioning and narrative self-construction in the first session of psychodynamic-interpersonal psychotherapy

The purpose of this study is to identify possible session one indicators of end of treatment psychotherapy outcome using the framework of three types of interactional positioning; client’s self-positioning, client’s positioning between narrated self and different partners, and the positioning between client and therapist. Three successful cases of 8-session psychodynamic-interpersonal (PI) therapy were selected on the basis of client Beck Depression Inventory scores. One unsuccessful case was also selected against which identified patterns could be tested. The successful clients were more descriptive about their problems and demonstrated active rapport-building, while the therapist used positionings expressed by the client in order to explore the positionings developed between them during therapy. The unsuccessful case was characterized by lack of positive self-comment, minimization of agentic self-capacity, and empathy-disrupting narrative confusions. We conclude that the theory of interactional positioning has been useful in identifying patterns worth exploring as early indicators of success in PI therapy

Hard Photodisintegration of a Proton Pair

We present a study of high energy photodisintegration of proton-pairs through the γ + 3He → p + p + n channel. Photon energies, Eγ , from 0.8 to 4.7 GeV were used in kinematics corresponding to a proton pair with high relative momentum and a neutron nearly at rest. The s−11 scaling of the cross section, as predicted by the constituent counting rule for two nucleon photodisintegration, was observed for the first time. The onset of the scaling is at a higher energy and the cross section is significantly lower than for deuteron (pn pair) photodisintegration. For Eγ below the scaling region, the scaled cross section was found to present a strong energy-dependent structure not observed in deuteron photodisintegration

Switching between different vortex states in 2-dimensional easy-plane magnets due to an ac magnetic field

Using a discrete model of 2-dimensional easy-plane classical ferromagnets, we propose that a rotating magnetic field in the easy plane can switch a vortex from one polarization to the opposite one if the amplitude exceeds a threshold value, but the backward process does not occur. Such switches are indeed observed in computer simulations.Comment: 4 pages, 4 figures, submitted to Phys. Rev. Let

Reflections from behind the screen: avoiding therapeutic rupture when utilising reflecting teams

Parker, N., & O'Reilly, M. (2013). Reflections from behind the screen: avoiding therapeutic rupture when utilising reflecting teams. The Family Journal: Counseling for Couples and Families, 21(2), 170-179. https://doi.org/10.1177/1066480712466810. Copyright © 2013 SAGE. Reprinted by permission of SAGE Publications.Since Tom Andersen developed the use of reflecting teams to facilitate the progress and process of family therapy, little empirical evidence has emerged regarding their effectiveness or use in therapeutic practice. Reflecting teams are typically embraced by family therapists as a positive mechanism for enhancing practice and thus it is important that research explores how they are utilized. In this article, we draw upon videotaped data of naturally occurring family therapy from the United Kingdom. Using conversation analysis, we identified three performative actions related to interrupting the therapeutic conversation to consult with a reflecting team. We found that therapists had difficulty exiting therapy, that on some occasions exit was hindered, and that there were disturbances in feeding back the reflections of the team. By examining the use of teams in real practice, we were able to make a number of recommendations for practicing family therapists to facilitate the use of this valuable resource

Low Q^2 measurements of the proton form factor ratio mupGE/GMmu_p G_E / G_M

We present an updated extraction of the proton electromagnetic form factor ratio, mu_p G_E/G_M, at low Q^2. The form factors are sensitive to the spatial distribution of the proton, and precise measurements can be used to constrain models of the proton. An improved selection of the elastic events and reduced background contributions yielded a small systematic reduction in the ratio mu_p G_E/G_M compared to the original analysis.Comment: 12 pages, 5 figures, archival paper for proton form factor extraction from Jefferson Lab "LEDEX" experimen

The Proton Elastic Form Factor Ratio at Low Momentum Transfer

High precision measurements of the proton elastic form factor ratio have been made at four-momentum transfers, Q^2, between 0.2 and 0.5 GeV^2. The new data, while consistent with previous results, clearly show a ratio less than unity and significant differences from the central values of several recent phenomenological fits. By combining the new form-factor ratio data with an existing cross-section measurement, one finds that in this Q^2 range the deviation from unity is primarily due to GEp being smaller than the dipole parameterization.Comment: 5 pages, 2 figure