Calibration of human locomotion and models of perceptual-motor organization.

People coordinate the force and direction of skilled actions with target locations and adjust the calibrations to compensate for changing circumstances. Are the adjustments globally organized (adjusting a particular action to fit a particular circumstance would generalize to all actions in the same circumstance); anatomically specific (every effector is adjusted independently of others); or functional (adjustments would generalize to all actions serving the same goal and generating the same perceptible consequences)? Across 10 experiments, changes in the calibration of walking, throwing, and turning-in-place were induced, and generalization of changes in calibration to functionally related and unrelated actions were tested. The experiments demonstrate that humans rapidly adjust the calibration of their walking, turning, and throwing to changing circumstances, and a functional model of perceptual-motor organization is suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bayesian integration of spatial information.

Spatial judgments and actions are often based on multiple cues. The authors review a multitude of phenomena on the integration of spatial cues in diverse species to consider how nearly optimally animals combine the cues. Under the banner of Bayesian perception, cues are sometimes combined and weighted in a near optimal fashion. In other instances when cues are combined, how optimal the integration is might be unclear. Only 1 cue may be relied on, or cues may seem to compete with one another. The authors attempt to bring some order to the diversity by taking into account the subjective discrepancy in the dictates of multiple cues. When cues are too discrepant, it may be best to rely on 1 cue source. When cues are not too discrepant, it may be advantageous to combine cues. Such a dual principle provides an extended Bayesian framework for understanding the functional reasons for the integration of spatial cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nordihydroguaiaretic acid blocks secretory and endocytic pathways in human dendritic cells

The authors evaluated the clinical longevity of a brand of porcelain veneers and the accompanying cementation system. Fifty-nine porcelain veneers were prepared and placed in 12 patients by one practitioner and evaluated by two evaluators using modified Ryge criteria at baseline and 12 months. Fifty-three veneers were evaluated similarly at 48 months. Plaque index and gingival index scores were recorded as well. At 48 months, the veneers had stable color, all margins were clinically acceptable, there was no secondary caries and the patients reported no sensitivity.     

Optimum synthesis of function generators involving derivative constraintsLa synthese optimale de generateurs de fonction impliquant des derivees comme contraintes

Presented in this article is the method of optimum synthesis of mechanisms satisfying derivatives of the generated displacements along with the displacements at a discrete set of design positions. Although the method is illustrated for the synthesis of four-bar function generators, where the first and second derivatives of the generated functions are also generated at all or some of the design positions in order to increase the efficiency of approximating the generated function, the method is readily applicable for the synthesis of mechanisms to generate paths and rigid-body positions satisfying path velocities, path accelerations, and rigid-body angular velocities. Mechanisms of precision control units, vibratory feeders and conveyors, transfer robots and mechanical arms, and linkages replacing noncircular gear drives require the application of such synthesis techniques involving derivatives of the generated displacements.     

Access to knowledge of spatial structure at novel points of observation.

Adults were asked to judge the self-to-object directions in a room from novel points of observation that differed from their actual point at times only by a rotation and at other times only by a translation. The results show for the rotation trials that the errors and latencies when a novel point was imagined were worse than the baseline responses from their actual points of observation, and the latencies varied as a function of the magnitude of the to-be-imagined rotation. For the translation trials, on the other hand, the errors and latencies when a novel point was imagined were comparable to the baseline responses from their actual point and did not vary significantly across the different imagined station points. The evidence indicates that subjects know the object-to-object relations directly, without going through the origin of a coordinate system. In addition, similarities in processing during imagination on the one hand, and perception and action on the other are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Editor’s introduction to the APA centennial series.

Nineteen ninety-two is the 100th anniversary of the founding of American Psychological Association. To mark this occasion, Developmental Psychology will publish a series of articles during the year that examine the contributions of our intellectual forebears. The major goals of these articles are to articulate the ways in which these theorists have influenced our current theory and research in the field of developmental psychology and to provide an assessment of their contribution to our field in light of our current knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Finding the Critical Facts: Children's Visual Scan Patterns When Solving Story Problems That Contain Irrelevant Information.

Two experiments were conducted to understand the processes through which 5th graders discriminate relevant from irrelevant information when solving mathematical story problems. Visual scanning was recorded and coded as directed toward relevant information, irrelevant information, the question, workspace, and elsewhere. Experiment 1 focused on the effects of irrelevant numerical information, and Experiment 2 focused on irrelevant qualitative information. The visual scanning results showed that higher achieving and lower achieving students generally used question-guided comparisons of the relevant and irrelevant information when they succeeded. A 2nd effective strategy was to discriminate during their initial reading of the problems. In addition, whereas higher achieving students flexibly varied their visual scanning to fit with problem difficulty, the lower achievers showed less flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Humoral and cellular immune responses in the murine respiratory tract following oral immunization with cholera toxin or Escherichia coli heat-labile enterotoxin

Cholera toxin (CT) and Escherichia coli heat-labile enterotoxin (LT) are the strongest mucosal immunogens identified to date and are also good adjuvants when given orally together in combination with unrelated antigens. We used these potent immunogens to monitor local and systemic immune responses following oral immunization of BALB/c mice, and compared their action on the following: (a) immunoglobulin production rates (IgG, IgM and IgA) in mucosal inductive (Peyer's patches-PPs), effector (intestinal lamina propria-LP, respiratory tract) and systemic (spleen) sites; (b) analysis of systemic antigen-specific antibodies (IgG subclasses, IgA and IgE); (c) time monitoring of fecal anti-CT and anti-LT antibodies, and (d) in vivo relevance of interleukin-6 (IL-6) to mucosal responses. Both mucosal immunogens elicited specific antibody responses (IgA, IgG) not only in the gastrointestinal tract (PP's and intestinal LP), but also in the respiratory tract and spleens of orally immunized mice. These mucosal responses were accompained by elevated secretion of IL-6 in all investigated tissues, indicating involvement of this cytokine in B-cell maturation processes. Furthermore, oral immunization with CT and LT induced elevated serum titers of IgG1 followed by IgG2a, IgG2b, IgG3 and IgA, while high antigen-specific IgA and IgG1 responses were found in fecal extracts. These findings illustrate the action of orally administered CT and LT, respectively, on several humoral and cellular immune responses not only at the gastrointestinal tract, the application site, but also in distant mucosal effector sites such as the respiratory tract. These data suggest the potential use of these mucosal adjuvants in oral immunization strategies to improve the local immune response in remote mucosal tissues, in accordance with the concept of a common mucosa-associated immune system.