Effects of 24-hour ambulatory blood pressure monitoring on daily activities.

Compared the self-monitored activities, locations, and postural positions of 28 hypertensives while they wore an alarm watch and then while they wore a 24-hr ambulatory blood pressure monitor (ABPM) to see if wearing the ABPM led to alterations in behavior. Significant differences were found in frequency of being at home or in miscellaneous settings; in standing and reclining positions; and in mental, physical, and miscellaneous activities between the 2 occasions. For the most part, differences were in the direction of showing lower overall blood pressure while wearing the ABPM than would have been found at the same time while wearing the watch. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stomach acid secretion in submissive and aggressive rats.

Conducted 4 experiments with 60 female and 162 male Long-Evans rats to determine whether aggressive and submissive behavior are related to either an increase or a decrease in gastric secretion. In Exp I, intruder rats placed in an established male–female colony and attacked by a dominant alpha male secreted less acid than intruders exposed to nonaggressive males and females. In Exp II, intruders exposed to attack and subsequently returned to the encounter site, but protected from physical attack, still demonstrated a gastric hyposecretion. Ss with chronic gastric cannulas in Exp III also revealed an acid inhibition when attacked and later when exposed to, but protected from, attack. Both intruders and attacking males were prepared with gastric cannulas in Exp IV. Both demonstrated secretory inhibition following attack and attack-protected sessions. The inhibitory effect was greater and more persistent for intruders than for aggressive Ss. It is suggested that the inhibition occurring during the attack-protected sessions may have been mediated by some conditioning processes, and other possible associative mechanisms, including a learning model or a direct sensory model, are discussed. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predicting human behavior: Comparing idiographic, nomothetic, and agentic methodologies.

Several longstanding issues in psychological research (e.g., self-determination vs. nonagentic determination in human action and nomothetic vs. idiographic research approaches) are explored. Reasons are presented that suggest why agentic and idiographic approaches (in combination with the more typical nomothetic, nonagentic studies) may enhance the predictive accuracy of psychological experiments. A study on the daily exercise behavior of 42 subjects over a 60-day period is presented and analyzed from 3 perspectives: nonagentic–nomothetic, nonagentic–idiographic, and agentic–nomothetic. The results suggest that substantial dividends in predictive accuracy accrue when nontraditional research perspectives are entertained. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of the Matrix and Matrix Bonding on the Creep Behavior of a Unidirectional Carbon–Carbon Composite

Creep tests were performed on single-bundle carbon–carbon specimens at high temperatures (>2310°C) and at high stress levels (>770 MPa). It was found that the creep was very strongly dependent on the filament–matrix interfacial bond. When the bond was good, the typical creep was 3.6% after 5.9 h with the primary creep a high percentage of the total deformation. When the bond was absent (dry bundle), rupture with strain was approximately 140%, and it occurred after only 0.39 h. The marked improvement in creep resistance is attributed to the ability of the matrix to distribute loads evenly and to produce a plastic flow inhibiting triaxial stress state among the filaments.     

Intelligent temporal subsampling of American Sign Language using event boundaries.

How well can a sequence of frames be represented by a subset of the frames? Video sequences of American Sign Language (ASL) were investigated in two modes: dynamic (ordinary video) and static (frames printed side by side on the display). An activity index was used to choose critical frames at event boundaries, times when the difference between successive frames is at a local minimum. Sign intelligibility was measured for 32 experienced ASL signers who viewed individual signs. For full gray-scale dynamic signs activity-index subsampling yielded sequences that were significantly more intelligible than when every mth frame was chosen. This result was even more pronounced for static images. For binary images, the relative advantage of activity subsampling was smaller. We conclude that event boundaries can be defined computationally and that subsampling from event boundaries is better than choosing at regular intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tables of the Inverse Laplace Transform of the Function [... formula ...]

The inverse transform, g(t) = ?^?1(e^?sβ), 0 < β < 1, is a stable law that arises in a number of different applications in chemical physics, polymer physics, solid-state physics, and applied mathematics. Because of its important applications, a number of investigators have suggested approximations to g(t). However, there have so far been no accurately calculated values available for checking or other purposes. We present here tables, accurate to six figures, of g(t) for a number of values of β between 0.25 and 0.999. In addition, since g(t), regarded as a function of β, is uni-modal with a peak occurring at t = t_max we both tabulate and graph t_max and 1/g(t_max) as a function of β, as well as giving polynomial approximations to 1/g(t_max).     

A simplified nonlinear stability analysis of an imperfect rectangular two-bar frame

A simplified nonlinear stability analysis for moderately large rotations and small strains is performed on a rectangular two-bar frame subjected to a concentrated eccentrically applied joint load. Such a simplification consisting of adopting linear kinematic relations leads to very reliable results for the initial postbuckling path in the vicinity of the critical point of the above imperfect frame. The existence of an asymmetric bifurcation point is thoroughly discussed and a direct evaluation of the bifurcational load is readily obtained. Using this technique the effect of imperfection sensitivity is also addressed. A qualitative analysis associated with the physical phenomenon yields a substantial reduction of the computational work. The efficiency and reliability of this approximate nonlinear stability analysis proposed herein is illustrated by means of several examples for which a lot of numerical results based on a more accurate nonlinear analysis are available.