Improving Cognitive-Behavioral Therapy Homework Adherence with Change Talk and Commitment Language: A Cognitive Dissonance Perspective of Behavioral Change

Adherence to homework assigned during cognitive-behavioral therapy (CBT) is an important factor contributing to positive outcomes. However, rates of adherence are poor, limited evidence supporting methods to improve adherence is limited. The current study aimed to develop and test an intervention designed to promote CBT homework adherence based on cognitive dissonance theory. Patients participating in outpatient CBT were randomly assigned to either an experimental or a control condition. In the experimental condition, participants engaged in an induced-compliance procedure eliciting change talk targeting the recommended homework activity. The control condition consisted of treatment as usual. Owing to limited sample size (n = 14), statistical analysis lacked sufficient power to confirm hypotheses; however, notable effect sizes were observed trending in support of the study hypotheses predicting greater rates of homework adherence in the experimental condition. These data, in conjunction with the large body of evidence directly supporting cognitive dissonance theory as an explanation of attitude and behavioral change, invites future studies to continue to explore the use of cognitive dissonance theory in clinical settings to promote attitude and behavioral change

On the covariance of the Dirac-Born-Infeld-Myers action

A covariant version of the non-abelian Dirac-Born-Infeld-Myers action is presented. The non-abelian degrees of freedom are incorporated by adjoining to the (bosonic) worldvolume of the brane a number of anticommuting fermionic directions corresponding to boundary fermions in the string picture. The proposed action treats these variables as classical but can be given a matrix interpretation if a suitable quantisation prescription is adopted. After gauge-fixing and quantisation of the fermions, the action is shown to be in agreement with the Myers action derived from T-duality. It is also shown that the requirement of covariance in the above sense leads to a modified WZ term which also agrees with the one proposed by Myers.Comment: 18 pages. Minor alterations to the text; references adde

Derived Bedrock Elevations, Strain Rates and Stresses from Measured Surface Elevations and Velocities - Jakobshavns-Isbrae, Greenland

Jakobshavns Isbrae (69 degrees 10\u27N, 49 degrees 5\u27W) drains about 6.5% of the Greenland ice sheet and is the fastest ice stream known. The Jakobshavns Isbrae basin of about 10 000 km(2) was mapped photogrammetrically from four sets of aerial photography, two taken in July 1985 and two in July 1986. Positions and elevations of several hundred natural features on the ice surface were determined for each epoch by photogrammetric block-aerial triangulation, and surface velocity vectors were computed from the positions. The two flights in 1985 yielded the best results and provided most common points (716) for velocity determinations and are therefore used in the modeling studies. The data from these irregularly spaced points were used to calculate ice elevations and velocity vectors at uniformly spaced grid paints 3 km apart by interpolation. The field of surface strain rates was then calculated from these gridded data and used to compute the field of surface deviatoric stresses, using the flow law of ice, for rectilinear coordinates, X, Y pointing eastward and northward. and curvilinear coordinates, L, T pointing longitudinally and transversely to the changing ice-flow direction. Ice-surface elevations and slopes were then used to calculate ice thicknesses and the fraction of the ice velocity due to basal sliding. Our calculated ice thicknesses are in fair agreement with an ice-thickness map based on seismic sounding and supplied to us by K. Echelmeyer. Ice thicknesses were subtracted from measured ice-surface elevations to map bed topography. Our calculation shows that basal sliding is significant only in the 10-15 km before Jakobshavns Isbrae becomes afloat in Jakobshavns IsfJord

Decay Modes of Intersecting Fluxbranes

Just as the single fluxbrane is quantum mechanically unstable to the nucleation of a locally charged spherical brane, so intersecting fluxbranes are unstable to various decay modes. Each individual element of the intersection can decay via the nucleation of a spherical brane, but uncharged spheres can also be nucleated in the region of intersection. For special values of the fluxes, however, intersecting fluxbranes are supersymmetric, and so are expected to be stable. We explicitly consider the instanton describing the decay modes of the two--element intersection (an F5-brane in the string theory context), and show that in dimensions greater than four the action for the decay mode of the supersymmetric intersection diverges. This observation allows us to show that stable intersecting fluxbranes should also exist in type 0A string theory.Comment: 19 pages, 6 figures. References adde

Closed timelike curves and geodesics of Godel-type metrics

It is shown explicitly that when the characteristic vector field that defines a Godel-type metric is also a Killing vector, there always exist closed timelike or null curves in spacetimes described by such a metric. For these geometries, the geodesic curves are also shown to be characterized by a lower dimensional Lorentz force equation for a charged point particle in the relevant Riemannian background. Moreover, two explicit examples are given for which timelike and null geodesics can never be closed.Comment: REVTeX 4, 12 pages, no figures; the Introduction has been rewritten, some minor mistakes corrected, many references adde

Chain of refined perception in self-optimizing assembly of micro-optical systems

Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements – especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base

The polarization of F1 strings into D2 branes: "Aut Caesar aut nihil"

We give matrix and supergravity descriptions of type IIA F-strings polarizing into cylindrical D2 branes. When a RR four-form field strength F_4 is turned on in a supersymmetric fashion (with 4 supercharges), a complete analysis of the solutions reveals the existence of a moduli space of F1 -> D2 polarizations (Caesar) for some fractional strengths of the perturbation, and of no polarization whatsoever (nihil) for all other strengths of the perturbation. This is a very intriguing phenomenon, whose physical implications we can only speculate about. In the matrix description of the polarization we use the Non-Abelian Born-Infeld action in an extreme regime, where the commutators of the fields are much larger than 1. The validity of the results we obtain, provides a direct confirmation of this action, although is does not confirm or disprove the symmetrized trace prescription.Comment: 14 page