Spatial Sampling Strategies with Multiple Scientific Frames of Reference

We study the spatial sampling strategies employed by field scientists studying aeolian processes, which are geophysical interactions between wind and terrain. As in geophysical field science in general, observations of aeolian processes are made and data gathered by carrying instruments to various locations and then deciding when and where to record a measurement. We focus on this decision-making process. Because sampling is physically laborious and time consuming, scientists often develop sampling plans in advance of deployment, i.e., employ an offline decision-making process. However, because of the unpredictable nature of field conditions, sampling strategies generally have to be updated online. By studying data from a large field deployment, we show that the offline strategies often consist of sampling along linear segments of physical space, called transects. We proceed by studying the sampling pattern on individual transects. For a given transect, we formulate model-based hypotheses that the scientists may be testing and derive sampling strategies that result in optimal hypothesis tests. Different underlying models lead to qualitatively different optimal sampling behavior. There is a clear mismatch between our first optimal sampling strategy and observed behavior, leading us to conjecture about other, more sophisticated hypothesis tests that may be driving expert decision-making behavior. For more information: Kod*la

Airborne Lidar measurements of aerosols, mixed layer heights, and ozone during the 1980 PEPE/NEROS summer field experiment

A detailed summary of the NASA Ultraviolet Differential Absorption Lidar (UV DIAL) data archive obtained during the EPA Persistent Elevated Pollution Episode/Northeast Regional Oxidant Study (PEPE/NEROS) Summer Field Experiment Program (July through August 1980) is presented. The UV dial data set consists of remote measurements of mixed layer heights, aerosol backscatter cross sections, and sequential ozone profiles taken during 14 long-range flights onboard the NASA Wallops Flight Center Electra aircraft. These data are presented in graphic and tabular form, and they have been submitted to the PEPE/NEROS data archive on digital magnetic tape. The derivation of mixing heights and ozone profiles from UV Dial signals is discussed, and detailed intercomparisons with measurements obtained by in situ sensors are presented

The evaluation of a shuttle borne lidar experiment to measure the global distribution of aerosols and their effect on the atmospheric heat budget

A shuttle-borne lidar system is described, which will provide basic data about aerosol distributions for developing climatological models. Topics discussed include: (1) present knowledge of the physical characteristics of desert aerosols and the absorption characteristics of atmospheric gas, (2) radiative heating computations, and (3) general circulation models. The characteristics of a shuttle-borne radar are presented along with some laboratory studies which identify schemes that permit the implementation of a high spectral resolution lidar system

How can geologic decision making under uncertainty be improved?

Financial support: This research has been supported by the National Science Foundation (Science of Learning Collaborative Network (grant no. 1640800), National Robotics Initiative (grant no. 1734365), and Future of Work at the Human Technology Frontier (grant no. 1839705)) and the Royal Society of Edinburgh (Research sabbatical grant).Peer reviewedPublisher PD

Lunar surface mechanical properties — Surveyor 1

Engineering telemetry data and lunar surface photographs by Surveyor 1 have been evaluated for information on the mechanical properties of the lunar surface material at the Surveyor 1 landing site. Based primarily on photographic evidence, estimates of soil density, cohesion, and other soil characteristics are presented. Also, the mechanisms in which the lunar material is believed to have failed under the footpad impacts are discussed. Because dynamic soil reactions cannot be interpreted directly from the available data, a comparative study using computer-simulated landings was initiated. Preliminary results of this study, which is still in progress, are presented

Cholinergic mechanisms in schizophrenia: Relationship to sleep-EEG abnormalities and positive/ negative symptoms

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30875/1/0000539.pd

Association between abnormal REM sleep and negative symptoms in schizophrenia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28038/1/0000477.pd

Effect of neuroleptic treatment on polysomnographic measures in schizophrenia

To study the effects of neuroleptic therapy on sleep EEG variables in schizophrenia, as well as the clinical correlates of these variables, we performed polysomnographic (PSG) studies on 14 schizophrenic inpatients before and during neuroleptic therapy. Sleep continuity measures improved after 3 weeks of neuroleptic therapy, showing decreased sleep latency and improved sleep efficiency. REM latency increased with treatment, although half the patients continued to exhibit REM latencies less than 60 min. Other sleep stages and measures of REM sleep (density, activity, number of periods) did not appear to change with neuroleptic treatment. At baseline, REM latency had strong negative correlations with BPRS and SANS scores, but with 3 weeks of such treatment, this association disappeared. Further work is needed to distinguish direct medication effects from the effects of the changing clinical state on PSG measures.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29068/1/0000102.pd

Cholinergic mechanisms and REM sleep abnormalities in schizophrenia

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30304/1/0000706.pd