CATTELL (2), Lentz (J), Mailer (6) and others, arguing from the observation that family size is inversely related to test performance, education and socio-economic level, have contended that the mean I.Q. of the population is declining at the rate of three or four points per generation. In contrast, data collected by the Personnel Research Section, AGO, during the closing months of World War II...

Quantum tunneling rates through a barrier separating two-dimensional, symmetric, double-well potentials are shown to depend on the classical dynamics of the billiard trajectories in each well and, hence, on the shape of the wells. For shapes that lead to regular (integrable) classical dynamics the tunneling rates fluctuate greatly with eigenenergies of the states sometimes by over two orders of...

We present experimental coherent two-dimensional Fourier-transform spectra of Wannier exciton resonances in semiconductor quantum wells generated by a pulse sequence that isolates two-quantum coherences. By measuring the real part of the signals, we determine that the spectra are dominated by two-quantum coherences due to mean-field many-body interactions, rather than bound biexcitons. Simulati...

Participants (N = 280) reviewed 20 fictional research summaries of studies examining the relation between similarity and attraction. Although there were some inconsistencies across the fictional studies, there was a positive relation overall (d = 0.2). The authors manipulated the salience of the titles and the serial order in which the studies were presented without changing the results of the ...

Measurements of coherent electron spin dynamics in Ga1-xMnxAs/Al0.4Ga0.6As quantum wells with 0.0006%<x<0.03% show an antiferromagnetic (negative) exchange between s-like conduction band electrons and electrons localized in the d shell of the Mn2+ impurities. The magnitude of the s-d exchange parameter, N0alpha, varies as a function of well width indicative of a large and negative contribution ...

Durlak and Wells (1997) provide a pivotal appraisal of prevention research on children and adolescents. Their meta-analytic approach has the advantages of reducing scientific misjudgments based on single studies, and providing a more balanced evaluation of impact of various interventions; it provides an opportunity for hypothesis finding helps set methodological standards, allows assessment of ...

The cities of Bristol and Bath have played an eminent role in the history of mental handicap. Unfortunately, documentation is rather scanty, particu larly on the pre and post Reformation era but much more is known about the Holy Cross Hospital in Bath, perhaps the oldest mental handicap hospital in Great Britain. The Romans contributed to its foundations when they built Fossway Road on the outs...

In two separate shallow field experiments, at two distance scales, we have used continuous monitoring to estimate the effect of barometric pressure on crosswell travel time and thereby calibrated the stress sensitivity of the rock volume between the wells. In a 3 m experiment we found a stress sensitivity of 10/Pa while in a 30 m experiment the sensitivity was 5 x 10 /Pa. Results from a deeper ...

An investigation to compare the efficiency of landfill gas collection systems with different well numbers (one, two or four) and configurations (vertical or horizontal) has been conducted. The study has shown that with an increasing number of wells, the gas collection rate and efficiency are enhanced and the gas flux at the surface also becomes more uniform. In addition, the study has also sugg...

Agent-based stochastic models for finite populations have recently received much attention in the game theory of evolutionary dynamics. Both the ultimate fixation and the pre-fixation transient behavior are important to a full understanding of the dynamics. In this paper, we study the transient dynamics of the well-mixed Moran process through constructing a landscape function. It is shown that ...