Computability of Countable Subshifts in One Dimension

We investigate the computability of countable subshifts in one dimension, and their members. Subshifts of Cantor?CBendixson rank two contain only eventually periodic elements. Any rank two subshift in 2^? is decidable. Subshifts of rank three may contain members of arbitrary Turing degree. In contrast, effectively closed ( $\Pi^{0}_{1}$ ) subshifts of rank three contain only computable elements, but $\Pi^{0}_{1}$ subshifts of rank four may contain members of arbitrary $\Delta^{0}_{2}$ degree. There is no subshift of rank ??+1.     

Interactive display of isosurfaces with global illumination

In many applications, volumetric data sets are examined by displaying isosurfaces, surfaces where the data, or some function of the data, takes on a given value. Interactive applications typically use local lighting models to render such surfaces. This work introduces a method to precompute or lazily compute global illumination to improve interactive isosurface renderings. The precompiled illumination resides in a separate volume and includes direct light, shadows, and intersections. Using this volume, interactive globally illuminated renderings of isosurfaces become feasible while still allowing dynamic manipulation of lighting, viewpoint and isovalue.     

Managing what you measure: creating outcome-driven systems of care for youth with serious emotional disturbances

This article presents the California System of Care Model for youth with severe emotional disturbances as an illustration of how ongoing assessment of the costs and outcomes of service delivery can be an integral part of a service delivery model. The core of this model, developed initially in Ventura County, California, is a five-step planning process that guides care system development and implementation. The implications of each stage of the planning process for evaluation and feedback at the child, family, and system levels are highlighted. A set of principles for selecting outcome measures deriving from the planning process are also presented that, in conjunction with the planning model, serve as guidelines for establishing outcome measures within care systems. The resulting specific plan for measuring system- and client-level outcomes deriving from this process, along with challenges to the implementation of the outcome management plan, is described.     

Molecular recognition of DNA–protein complexes: A straightforward method combining scanning force and fluorescence microscopy

Combining scanning force and fluorescent microscopy allows simultaneous identification of labeled biomolecules and analysis of their nanometer level architectural arrangement. Fluorescent polystyrene nano-spheres were used as reliable objects for alignment of optical and topographic images. This allowed the precise localization of different fluorescence particles within complex molecular assemblies whose structure was mapped in nanometer detail topography. Our experiments reveal the versatility of this method for analysis of proteins and protein–DNA complexes.     

Randomized trial of a gatekeeper program for suicide prevention: 1-year impact on secondary school staff.

Gatekeeper-training programs, designed to increase identification and referral of suicidal individuals, are widespread but largely untested. A group-based randomized trial with 32 schools examined impact of Question, Persuade, Refer (QPR) training on a stratified random sample of 249 staff with 1-year average follow-up. To test QPR impact, the authors introduced and contrasted 2 models of gatekeeper-training effects in a population: gatekeeper surveillance and gatekeeper communication. Intent-to-treat analyses showed that training increased self-reported knowledge (effect size [ES] = 0.41), appraisals of efficacy (ES = 1.22), and service access (ES = 1.07). Training effects varied dramatically. Appraisals increased most for staff with lowest baseline appraisals, and suicide identification behaviors increased most for staff already communicating with students about suicide and distress. Consistent with the communication model, increased knowledge and appraisals were not sufficient to increase suicide identification behaviors. Also consistent with the communication model were results from 2,059 8th and 10th graders surveyed showing that fewer students with prior suicide attempts endorsed talking to adults about distress. Skill training for staff serving as "natural gatekeepers" plus interventions that modify students' help-seeking behaviors are recommended to supplement universal gatekeeper training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mutational analysis of the Drosophila sister-chromatid cohesion protein ORD and its role in the maintenance of centromeric cohesion

The ord gene is required for proper segregation of all chromosomes in both male and female Drosophila meiosis. Here we describe the isolation of a null ord allele and examine the consequences of ablating ord function. Cytologically, meiotic sister-chromatid cohesion is severely disrupted in flies lacking ORD protein. Moreover, the frequency of missegregation in genetic tests is consistent with random segregation of chromosomes through both meiotic divisions, suggesting that sister cohesion may be completely abolished. However, only a slight decrease in viability is observed for ord null flies, indicating that ORD function is not essential for cohesion during somatic mitosis. In addition, we do not observe perturbation of germ-line mitotic divisions in flies lacking ORD activity. Our analysis of weaker ord alleles suggests that ORD is required for proper centromeric cohesion after arm cohesion is released at the metaphase I/anaphase I transition. Finally, although meiotic cohesion is abolished in the ord null fly, chromosome loss is not appreciable. Therefore, ORD activity appears to promote centromeric cohesion during meiosis II but is not essential for kinetochore function during anaphase.     

Theoretical model for intermeshing twin screw extruders: Axial velocity profile for shallow channels

Positive displacement intermeshing twin screw extruders have been analyzed by a simple model for flow in the channel formed by the screw root and screw flights. The model considers the down channel flow to be a combination of drage flow resulting from the relative motion of the barrel and screw and pressure flow resulting from the positive displacement action of the device. The pressure flow in this situation is distinguished from pressure flow in a single screw extruder in that the pressure forces induce flow toward the die for the twin screw model rather than away from the die as in a single screw extruder. Comparison of the down channel shear rate profile of apositive displacement twin screw extruder with that of a single screw extruder with no net flow reveals that they are identical but inverted with respect to channel depth. The model presented does not consider leakage between the twin screws or the rotational motion of the second screw.     

Dynamic compensation and decoupling for systems of uniform index 2

The design of ann-dimensional dynamic compensator for arbitrary pole placement for systems of dimension2nand uniform controllability and observability indexes 2 is considered in state space representation and frequency domain.