Three-dimensional database of subcortical electrophysiology for image-guided stereotactic functional neurosurgery

We present a method of constructing a database of intraoperatively observed human subcortical electrophysiology. In this approach, patient electrophysiological data are standardized using a multiparameter coding system, annotated to their respective magnetic resonance images (MRIs), and nonlinearly registered to a high-resolution MRI reference brain. Once registered, we are able to demonstrate clustering of like interpatient physiologic responses within the thalamus, globus pallidus, subthalamic nucleus, and adjacent structures. These data may in turn be registered to a three-dimensional patient MRI within our image-guided visualization program enabling prior to surgery the delineation of surgical targets, anatomy with high probability of containing specific cell types, and functional borders. The functional data were obtained from 88 patients (106 procedures) via microelectrode recording and electrical stimulation performed during stereotactic neurosurgery at the London Health Sciences Centre. Advantages of this method include the use of nonlinear registration to accommodate for interpatient anatomical variability and the avoidance of digitized versions of printed atlases of anatomy as a common database coordinate system. The resulting database is expandable, easily searched using a graphical user interface, and provides a visual representation of functional organization within the deep brain.     

Bed-Load Effects on Hydrodynamics of Rough-Bed Open-Channel Flows

The extent to which turbulent structure is affected by bed-load transport is investigated experimentally using a nonporous fixed planar bed comprising mixed-sized granular sediment with a d50 of 1.95?mm. Three different sizes of sediment (d50 = 0.77, 1.99, and 3.96?mm) were fed into the flow at two different rates (0.003 and 0.006?kg/m/s), and subsequently transported as bed load. Particle image velocimetry (PIV) was used to determine the turbulence characteristics over the fixed bed during clear water and sediment feed cases. Mean longitudinal flow velocities at any given depth were lower than their clear water counterparts for all but one of the mobile sediment cases. The exception was with the transport of fine grains at the higher feed rate. In this case, longitudinal mean flow velocities increased compared to the clear water condition. The coarse grains tended to augment bed roughness, but fine grains saturated the troughs and interstices in the bed topography, effectively causing the influence of bed irregularities to be smoothed. The PIV technique permitted examination of both temporal and spatial fluctuations in flow variables: therefore many results are presented in terms of double-averaged quantities (in temporal and spatial domains). In particular, the form-induced stress, which arises from spatially averaging the Reynolds averaged Navier–Stokes equations and is analogous to the Reynolds turbulent stress, contributed between 15 and 35% of the total measured shear stress in the roughness layer. Flow around protrusive roughness elements produced a significant proportion of the turbulent kinetic energy shear production, suggesting that this process is highly intermittent near rough beds.     

Detecting random, partially random, and nonrandom Minnesota Multiphasic Personality Inventory--Adolescent Protocols.

The ability of the Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A; J. N. Butcher et al., 1992) validity scales to detect random, partially random, and nonrandom MMPI-A protocols was investigated. Investigations included the Variable Response Inconsistency scale (VRIN), F, several potentially useful new F and VRIN subscales, and formulas F? - F? and F + F? + |F - F?|. Protocols completed by 150 adolescents at a juvenile court setting, screened for randomness with a matched-pair Millon Adolescent Clinical Inventory (MACI) or Jesness Inventory, were compared with 100 computer-generated, all-random protocols, and with 5 levels of partially random protocols. VRIN was the most effective scale in detecting all-random protocols; however, the optimum cutoff of ≥ 75 failed to identify 1/3 of them. Using the new scales, a decision algorithm was described that correctly classified 94%-95% of protocols as interpretable, partially interpretable, or uninterpretable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhancing general-purpose tools with multi-state previewing capabilities

General-purpose design tools can be applied to a wide variety of design problems, but the large number of unique states they are able to produce makes it difficult to find results most relevant to a specific design problem. Current interfaces exacerbate this problem by offering only a single preview of one potential future state. We introduce multi-state previewing tools to facilitate the process of generating, displaying, navigating, and evaluating multiple, potential future states simultaneously. Multi-state previewing tools specifically encode and automate higher-level design practices, such as exploring multiple alternatives, better aligning computer-based tools with design. In this paper, we synthesize a framework for this class of tools by combining and generalizing existing instantiations, then show how this framework can be used to guide the design, implementation, and further research of these tools.     

Deterministic Flow Routing and Oligopolistic Competition in Dynamic Data Networks: Modeling and Numerical Solution Using Multigrid Optimization Techniques

In this paper we study the dynamic telecommunications flow routing problem from two points of view: (1) that of a single firm attempting to operate its network efficiently, and (2) oligopolistic competition among several firms competing for network capacity and market share. The mathematical perspective is that of continuous time optimal control and infinite dimensional variational inequalities.     

Low-cost interactive active range finder

This paper describes a new type of low-cost interactive active range finder and illustrates the effect of introducing interactivity to the range-acquisition process. The new range finder consists of only one camera and a laser pointer to which three LEDs are attached. When a user scans the laser, the camera captures the image of spots (one from the laser and the others from LEDs), and triangulation is carried out using the camera's viewing direction and the optical axis of the laser. The user interaction allows the range finder to acquire range data in which the sampling rate varies across the object depending on the underlying surface structures. Moreover, the processes of separating objects from the background and/or finding parts in the object can be achieved using the operator's knowledge of the objects. Received: 24 August 1999 / Accepted: 26 May 2000 Published online: 18 June 2003 Correspondence to: M. Takatsuka (e-mail: masa@it.usyd.edu.au) This project was funded by a grant from the Australian Research Council.     

Play Therapy with Young Perfectionists.

Recent empirical research has supported a view of perfectionism as potentially adaptive as well as maladaptive. As a result, it is important to accurately assess the form of perfectionism before designing a treatment plan. Cognitive/Adlerian approaches to play therapy offer unique opportunities for assessing and treating maladaptive perfectionism in children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Person?×?Situation interaction in personality prediction: Some specifics of the person factor.

Attempted to determine if the multidimensionality of trait anxiety (A-Trait), as measured by the S–R Inventory of General Trait Anxiousness, was related to differential personality profiles in 278 undergraduates. Results of stepwise multiple linear regression analyses, using Rotter's Internal–External Locus of Control Scale, the California Psychological Inventory, the Fear of Negative Evaluation Scale, and the Interpersonal Trust Scale as predictor measures, confirmed the existence of distinct personality profiles for each of the 4 facets of A-Trait. Findings attest to the multidimensionality of the S–R Inventory of General Trait Anxiousness and to the importance of specifying the situation in the measurement of anxiety. (PsycINFO Database Record (c) 2010 APA, all rights reserved)