Role of the inertia tensor in haptically perceiving where an object is grasped.

When an object is held and wielded, a time-invariant quantity of the wielding dynamics is the inertia tensor Iij. Examination of Iij as a function of different locations at which a cylindrical object is grasped revealed that the off-diagonal components of Iij, the products of inertia, related most systematically to grip position. In 3 experiments, Ss wielded an occluded rod held at an intermediate point along its length and reproduced, with the other hand, the felt grip position on a visible rod. In Exp 1, the wielded rods were homogeneous; in Exps 2 and 3, weights were added on either side of the grasp, with different manners of grasp contrasted in Exp 3. In all 3 experiments, perceived hand position was predicted by Iij. Discussion is focused on the role of Iij's eigenvalues in perceiving the magnitudes of objects and Iij's eigenvectors in perceiving hand–object relations (e.g., position of grasp). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

B. F. Skinner: Au-delá de la controverse.

Discusses controversies surrounding the work of B. F. Skinner's influence on various theories of human and animal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comments on “Fully magnetic attitude control for spacecraft subject to gravity gradient”

The Lyapunov argument used in Wi niewski and Blanke, (Automatica 35 (1999) 1201) to establish asymptotic stability of a magnetic control law for an earth-orbiting spacecraft is incorrect. It is shown here that a small change to the assumed form of the control law can remedy the situation.     

Why psychologists don't think like philosophers.

H. H. Kendler (see record 1994-09190-001), in his article on psychology and the ethics of social policy, argues in part that ethical imperatives cannot be inferred from empirical data. This argument is cited in opposition to what is purported to be the position of the American Psychological Association on the abortion issue. It is suggested that PhD candidates in psychology be well versed in the philosophical issues and debates that are the foundation for the formation of ethical principles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive treatments for eating disorders.

Cognitive-behavioral therapy (CBT) is applicable to all eating disorders but has been most intensively studied in the treatment of bulimia nervosa (BN). CBT is designed to alter abnormal attitudes about body shape and weight, replace dysfunctional dieting with normal eating habits, and develop coping skills for resisting binge eating and purging. CBT is effective in reducing all core features of BN and shows good maintenance of therapeutic improvement. Although superior to therapy with antidepressant drugs, CBT has not been shown to be consistently superior to alternative psychological treatments. Different hypotheses about CBT's mechanisms of action are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Water absorption properties of phosphate glass fiber‐reinforced poly‐ϵ‐caprolactone composites for craniofacial bone repair

The moisture uptake of polymers and composites has increasing significance where these materials are specified for invasive, long‐term medical applications. Here we analyze mass gain and the ensuing degradation mechanisms in phosphate glass fiber reinforced poly‐?‐caprolactone laminates. Specimens were manufactured using in situ polymerization of ?‐caprolactone around a bed of phosphate glass fibers. The latter were sized with 3‐aminopropyltriethoxysilane to control the rate of modulus degradation. Fiber content was the main variable in the study, and it was found that the moisture diffusion coefficient increased significantly with increasing fiber volume fraction. Diffusion, plasticization, and leaching of constituents appear to be the dominant aspects of the process over these short‐term tests. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Diamino telechelic polybutadienes for solventless styrene-butadiene-styrene (SBS) triblock copolymer formation

High molecular weight, high functionality diamino telechelic polybutadienes (TPBs) were synthesized by ring-opening metathesis polymerization (ROMP) of 1,5-cyclooctadiene (COD) in the presence of a chain transfer agent, 1,8-dicyano-4-octene, followed by lithium aluminum hydride reduction. Melt coupling of diamino TPB with anhydride-terminated polystyrene (PS-anh) resulted in the formation of styrene-butadiene-styrene (SBS) triblock copolymers; ca. 80% maximum conversion of PS-anh was achieved within 30 s. The results from SAXS, TEM, and rheological measurements of the coupling products confirmed the formation of SBS triblock copolymers having lamellar morphology. A fluorescent-labeled PS-anh was used to study the coupling kinetics by diluting the reactants by the addition of non-functional PS.