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Preschoolers\u27 understanding of and social behavior to handicapped classmates.
Autonomous support for microorganism research in space
A preliminary design for performing on orbit, autonomous research on microorganisms and cultured cells/tissues is presented. An understanding of gravity and its effects on cells is crucial for space exploration as well as for terrestrial applications. The payload is designed to be compatible with the Commercial Experiment Transporter (COMET) launch vehicle, an orbiter middeck locker interface, and with Space Station Freedom. Uplink/downlink capabilities and sample return through controlled reentry are available for all carriers. Autonomous testing activities are preprogrammed with in-flight reprogrammability. Sensors for monitoring temperature, pH, light, gravity levels, vibrations, and radiation are provided for environmental regulation and experimental data collection. Additional experimental data acquisition includes optical density measurement, microscopy, video, and film photography. On-board full data storage capabilities are provided. A fluid transfer mechanism is utilized for inoculation, sampling, and nutrient replenishment of experiment cultures. In addition to payload design, representative experiments were developed to ensure scientific objectives remained compatible with hardware capabilities. The project is defined to provide biological data pertinent to extended duration crewed space flight including crew health issues and development of a Controlled Ecological Life Support System (CELSS). In addition, opportunities are opened for investigations leading to commercial applications of space, such as pharmaceutical development, modeling of terrestrial diseases, and material processing
Multiple Time Scales in Diffraction Measurements of Diffusive Surface Relaxation
We grew SrTiO3 on SrTiO3 (001) by pulsed laser deposition, using x-ray
scattering to monitor the growth in real time. The time-resolved small angle
scattering exhibits a well-defined length scale associated with the spacing
between unit cell high surface features. This length scale imposes a discrete
spectrum of Fourier components and rate constants upon the diffusion equation
solution, evident in multiple exponential relaxation of the "anti-Bragg"
diffracted intensity. An Arrhenius analysis of measured rate constants confirms
that they originate from a single activation energy.Comment: 4 pages, 3 figure
Observed Effects of a Changing Step-Edge Density on Thin-Film Growth Dynamics
We grew SrTiO3 on SrTiO3 [001] by pulsed laser deposition, while observing
x-ray diffraction at the (0 0 .5) position. The drop dI in the x-ray intensity
following a laser pulse contains information about plume-surface interactions.
Kinematic theory predicts dI/I = -4sigma(1-sigma), so that dI/I depends only on
the amount of deposited material sigma. In contrast, we observed experimentally
that |dI/I| < 4sigma(1-sigma), and that dI/I depends on the phase of x-ray
growth oscillations. The combined results suggest a fast smoothing mechanism
that depends on surface step-edge density.Comment: 4 figure
History in today\u27s business school
Members of the American Assembly of Collegiate Schools of Business were surveyed to determine to what extent the history of various business school subjects (accounting, economics, management, etc.) was a part of today\u27s curricula. Findings indicated widespread teaching of history and the feeling that more should be done. However, the findings also indicate that much of the current teaching is not being done in separate courses by professional historians or even those interested in history. Implications for curricula development are discussed
Accounting history in today\u27s business schools
Slocum and Sriram\u27s [2001] study of teaching accounting history found a decline from 1985-1997 in the number of courses with historical content at the doctoral and undergraduate level. Is this development a singular event for accounting or an example of what is happening in other business disciplines? Our study presents the results of a longitudinal and cross-disciplinary survey of members of AACSB International to determine the current state of the teaching of history in business schools. We find a similar decline in other business disciplines and offer suggestions about the relevance of history and steps that might be taken to encourage its study
Nearly strain-free heteroepitaxial system for fundamental studies of pulsed laser deposition: EuTiO3 on SrTiO3
High quality epitaxial thin-films of EuTiO3 have been grown on the (001)
surface of SrTiO3 using pulsed laser deposition. In situ x-ray reflectivity
measurements reveal that the growth is two-dimensional and enable real-time
monitoring of the film thickness and roughness during growth. The film
thickness, surface mosaic, surface roughness, and strain were characterized in
detail using ex situ x-ray diffraction. The thicnkess and composition were
confirmed with Rutherford Backscattering. The EuTiO3 films grow
two-dimensionally, epitaxially, pseudomorphically, with no measurable in-plane
lattice mismatch.Comment: 7 pages, 6 figure
Ecological Parameters of Coluber constrictor etheridgei, with Comparisons to Other Coluber constrictor Subspecies
In 1998, we conducted a radio-telemetry study of Coluber constrictor etheridgei (Tan Racer) in the Angelina National Forest in eastern Texas. Individuals were located once daily from 12 June to 14 August. We determined home-range size, movement distances, movement frequency, and habitat use for this short-term study. We also determined food habits of this population by examination of fecal samples. We compared these parameters to other Racer taxa in Utah (C. c. mormon [Western Yellow-bellied Racer]), Kansas (C. c. fl aviventris [Eastern Yellow-bellied Racer]), and South Carolina (C.c. priapus [Southern Black Racer]). Compared to these populations, Texas Racers exhibited larger home ranges and greater movement frequency and distances during the summer than Utah or Kansas populations, but approximately equal to those of the South Carolina population. Available data on food habits suggests that all populations are consumers of invertebrate and vertebrate prey. We hypothesize that the basic diet of C. constrictor is composed of invertebrates captured by active foraging in areas of abundant herbaceous vegetation, that differences in home-range size and movement distances result from variations in patchiness of suitable foraging habitat across populations, and that the proportion of vertebrate prey in the diet of Coluber populations increases as home-range size and movement distances increase due to increasing patchiness of foraging habitat, resulting in increasing encounters with vertebrate prey
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