Aging and individual differences in the development of skilled memory search performance.

We examined individual differences in measures of multiple intellectual abilities and performance on a pure memory search task over 5 experimental sessions. Old (n?=?104) and young (n?=?97) participants showed expected patterns of substantial improvement in memory search intercepts and slopes in consistently mapped (CM) conditions, relative to varied mapping (VM) conditions. Initial (unskilled) CM and VM memory search was highly correlated with a Semantic Memory Access Speed factor and moderately correlated with General Intelligence. Structural equation models showed that measures of Semantic Memory Access remained a strong predictor of skilled CM search performance in both age groups despite individual differences in CM memory search performance changes. These results indicate qualitative differences in the nature of automaticity between memory search and visual search and suggest age invariance in the mechanisms determining automaticity in memory search. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recent Advances with Glycidylamine Resins

A new procedure for the glycidylation of aromatic amines has been developed recently, which leads to resins of lower viscosity, longer shelf-life and higher purity than methods used previously. Resins made by the new process show considerable processing and applications advantages over those made by earlier methods. The new process has also made accessible high purity glycidyl derivatives of amines which have hitherto proved difficult to glycidylate effectively.     

Implications of N and C-terminal proximity for protein folding

We have investigated the proximity of the N and C termini in protein structures, and developed a model to test the theoretical possibility that proteins fold with their termini closely associated. On average, the distance between the termini is not significantly different from what would be expected based on chance. However, the theoretical model indicated that it is possible to greatly decrease the N-to-C terminal distance by allowing small (approximately six amino acid residues) solvent-accessible terminal fragments to move. Subsequent to this distance minimization method, more than 90% of the proteins studied had smaller-than-expected N-to-C distances, but only minor structural modification.     

E.p.r. studies of outburst-prone anthracite coal

Changes in the macroscopic structure of coal have been observed as an outburst-prone area is approached. Associated with this structural change was an increase in the concentration of paramagnetic centres. Initial results suggested that this increase was not due to variation in maceral content within the coal samples but to the mechano-chemical degradation of the coal as a result of tectonic forces applied over geological time.     

Unsteady viscous jet flow into stationary surroundings

The unsteady constant-property uniform pressure flow of a viscous laminar axisymmetric jet into stationary surroundings is analyzed with the aid of the boundary layer approximations and an integral method. Numerical solutions of the resulting non-linear system of equations are presented for the response of an initially steady jet to monotonic mass flow variations which are imposed at the initial axial station of the jet. Significant departures from quasi-steady behaviour arise for sufficiently large streamwise distances and/or rates of change of the boundary conditions. Among these effects are overshoots in mass and momentum flux, a dynamic effect on flow entrainment, and a tendency toward discontinous behavior. The influence of the kinematic viscosity on the transient flow is examined, and an estimate is made of the applicability of quasi-steady approximations in this problem.     

Effectiveness of cognitive-behavioral treatments in reducing Type A behavior among university faculty.

Investigated the effects of 2 treatments, cognitive-behavioral modification (CBM) and cognitive-behavioral modification plus assertiveness training (CBM/AT), in reducing Type A (coronary prone) behavior and related characteristics among 51 female and male 31–64 yr old faculty members. Ss had scored at or above the 60th percentile on the Jenkins Activity Survey. Ss were also given the State-Trait Anger Scale, the Rational Behavior Inventory, and the Manifest Hostility Content Scale. Findings indicate that both treatments were significantly more effective than a minimal treatment control in reducing self-reported Type A behavior, hostility, and irrational beliefs. However, the addition of assertiveness training in the CBM/AT treatment did not significantly increase its effectiveness in reducing the dependent variables, compared with the CBM treatment. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of prior exposure on conditioned taste aversion in the rat: Androgen- and estrogen-dependent events.

Studied the effects of preexposure and gonadal hormone manipulation on the extinction of a conditioned taste aversion in 198 male Sprague-Dawley rats. In Exp I, Ss were given 1 prior exposure to sucrose at some selected time (Days 4, 2, or 1) before a 2nd exposure (Day 0) to sucrose and a LiCl injection, or they were given only a single exposure (Day 0). Under single exposure, castrated Ss extinguished the aversion faster than either testosterone-treated castrated Ss or sham-operated Ss. In Exp II, estradiol, dihydrotestosterone, and testosterone were studied by using only a Day 1 preexposure condition. The testosterone-treated group maintained the aversion for the longest period, followed by dihydrotestosterone-treated, sham, castrated, and estradiol-treated groups. In Exp III, estradiol was administered alone or in combination with 2 doses of dihydrotestosterone. Findings indicate that the outcome of behavior was dependent on the ratio of estradiol to dihydrotestosterone, with variations in this ratio resulting in fast (estrogen effect) to slow (androgen effect) rates of extinction. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A lamellar model for analysis of liquid-liquid mixing

Two quantities, a_ν, intermaterial area per unit volume and s, striation thickness, are defined to describe the state of a system mixed or being mixed. These quantities are related to one another and to the fluid mechanics of mixing in Lagrangian and Eulerian frames of reference. The model considers that mechanical mixing is synonymous with deformation.An equation for rate of generation of intermaterial area is presented and integrated for systems of engineering interest. An upper bound for this rate of generation is obtained for the case of Newtonian incompressible fluids. Special attention is given to the microscale of mixing where reaction and diffusion occur.It is shown that diffusion and reaction can be combined into a single variable due to a particular choice of reference frame. In this way the necessary tools for analyzing liquid-liquid mixing are presented. The restrictions to this analysis are: (i) microscale can be represented by a lamellar structure, (ii) no surface tension effects, (iii) no instabilities at the microscale of mixing.