Strong genetic influences on the stability of autistic traits in childhood

Objective: Disorders on the autism spectrum, as well as autistic traits in the general population, have been found to be both highly stable across age and highly heritable at individual ages. However, little is known about the overlap in genetic and environmental influences on autistic traits across age and the contribution of such influences to trait stability itself. The present study investigated these questions in a general population sample of twins. Method: More than 6,000 twin pairs were rated on an established scale of autistic traits by their parents at 8, 9, and 12 years of age and by their teachers at 9 and 12 years of age. Data were analyzed using structural equation modeling. Results: The results indicated that, consistently across raters, not only were autistic traits stable, and moderately to highly heritable at individual ages, there was also a high degree of overlap in genetic influences across age. Furthermore, autistic trait stability could largely be accounted for by genetic factors, with the environment unique to each twin playing a minor role. The environment shared by twins had virtually no effect on the longitudinal stability in autistic traits. Conclusions: Autistic traits are highly stable across middle childhood and this stability is caused primarily by genetic factors

Experiments in Planetary and Related Sciences and the Space Station

Numerous workshops were held to provide a forum for discussing the full range of possible experiments, their science rationale, and the requirements on the Space Station, should such experiments eventually be flown. During the workshops, subgroups met to discuss areas of common interest. Summaries of each group and abstracts of contributed papers as they developed from a workshop on September 15 to 16, 1986, are included. Topics addressed include: planetary impact experimentation; physics of windblown particles; particle formation and interaction; experimental cosmochemistry in the space station; and an overview of the program to place advanced automation and robotics on the space station

Stress distribution and topography of Tellus Regio, Venus

The Tellus Regio area of Venus represents a subset of a narrow latitude band where Pioneer Venus Orbiter (PVO) altimetry data, line-of-sight (LOS) gravity data, and Venera 15/16 radar images have all been obtained with good resolution. Tellus Regio also has a wide variety of surface morphologic features, elevations ranging up to 2.5 km, and a relatively low LOS gravity anomaly. This area was therefore chosen in order to examine the theoretical stress distributions resulting from various models of compensation of the observed topography. These surface stress distributions are then compared with the surface morphology revealed in the Venera 15/16 radar images. Conclusions drawn from these comparisons will enable constraints to be put on various tectonic parameters relevant to Tellus Regio. The stress distribution is calculated as a function of the topography, the equipotential anomaly, and the assumed model parameters. The topography data is obtained from the PVO altimetry. The equipotential anomaly is estimated from the PVO LOS gravity data. The PVO LOS gravity represents the spacecraft accelerations due to mass anomalies within the planet. These accelerations are measured at various altitudes and angles to the local vertical and therefore do not lend themselves to a straightforward conversion. A minimum variance estimator of the LOS gravity data is calculated, taking into account the various spacecraft altitudes and LOS angles and using the measured PVO topography as an a priori constraint. This results in an estimated equivalent surface mass distribution, from which the equipotential anomaly is determined

AN IMPROVED ECONOMIC LAND CLASSIFICATION SYSTEM FOR SPATIAL LINEAR PROGRAMMING MODELS

Land Economics/Use,

RURAL ECONOMIC DEVELOPMENT FOR COMMUNITY SELF-RELIANCE

Community/Rural/Urban Development,

ADAPTIVE PLANNING UNDER PRICE UNCERTAINTY IN PORK PRODUCTION

Livestock Production/Industries, Risk and Uncertainty,

How to be ready for a Local Emphasis Program (LEP) inspection

Voluntary consultations are available that help prepare for an OSHA LEP inspection

So What? A Primer on Methods for Identifying, Measuring, and Analyzing Program Impacts and Outcomes

This paper offers insights on the need for increased program accountability and the benefits that arise from the use of better performance measures. Examples of impact and accountability reports are presented to highlight the best practices. Weaker impact reports are analyzed so as to emphasize more effective ways to demonstrate outputs and impact to funders