Passive geodetic satellite canister assemblies

Passive geodetic satellite /PAGEOS/ canister assemblie

When is an error not a prediction error? An electrophysiological investigation

A recent theory holds that the anterior cingulate cortex (ACC) uses reinforcement learning signals conveyed by the midbrain dopamine system to facilitate flexible action selection. According to this position, the impact of reward prediction error signals on ACC modulates the amplitude of a component of the event-related brain potential called the error-related negativity (ERN). The theory predicts that ERN amplitude is monotonically related to the expectedness of the event: It is larger for unexpected outcomes than for expected outcomes. However, a recent failure to confirm this prediction has called the theory into question. In the present article, we investigated this discrepancy in three trial-and-error learning experiments. All three experiments provided support for the theory, but the effect sizes were largest when an optimal response strategy could actually be learned. This observation suggests that ACC utilizes dopamine reward prediction error signals for adaptive decision making when the optimal behavior is, in fact, learnable

The Development and Validation of the Emporium Model Motivation Scale (EMMS)

The purpose of this research study was to begin the development and validation of a new survey instrument; the Emporium Model Motivation Scale (EMMS). The instrument is designed to be used as part of a more holistic evaluation of non-traditional student-centered mathematics courses or programs redesigned using the Emporium Model (E-Model). EdResearch suggested that the design of the E-Model environment was better suited to help students become more autonomy-natured (Williams, 2016). The present research was rooted in Self-determination Theory (SDT), which asserted that all individuals had a natural desire to strive for autonomy, competence, and relatedness in their social environments (Ryan & Deci, 2000; 2017). The research study consisted of a random sample of n = 463 respondents from both a U.S. community college and 4-year public university. Results of an Exploratory Factor Analysis (EFA) produced four parsimonious factor solutions that showed potential to be valid, highly reliable with (ω ≥ .89) and replicable across other samples or populations. The factors were analyzed using Polychoric correlations, with Unweighted Least Squares (ULS) extraction and Promax rotation. Correlational analysis, MANOVA, ANOVA, and Standard Multiple Regression were performed with accurate and reliable standardized factor score estimates. Overall results revealed statistically significant differences between the two institutions of higher learning across levels of the EMMS factors. Further analyses revealed that age was a statistically significant predictor of the EMMS factors and that older respondents were more autonomous and receptive of the E-Model design for course instruction

A specific gravity study of some of the Southeast Missouri lead ores and tailings

The object of this investigation was to study some of the Southeast Missouri lead ores and tailings to trace the freeing of galena through all of the screen sizes. It was also desired to determine the efficiency of recovery with the present treatment and, whether or not a change to finer crushing would be advisable. In order to isolate parts of different specific gravity in the ores and tailings, heavy liquids were used --Object of Investigation, page 2

A Chandra Survey of the X-ray Properties of Broad Absorption Line Radio-Loud Quasars

This work presents the results of a Chandra study of 21 broad absorption line (BAL) radio-loud quasars (RLQs). We conducted a Chandra snapshot survey of 12 bright BAL RLQs selected from SDSS/FIRST data and possessing a wide range of radio and CIV absorption properties. Optical spectra were obtained nearly contemporaneously with the Hobby-Eberly Telescope; no strong flux or BAL variability was seen between epochs. We also include in our sample 9 additional BAL RLQs possessing archival Chandra coverage. We compare the properties of (predominantly high-ionization) BAL RLQs to those of non-BAL RLQs as well as to BAL radio-quiet quasars (RQQs) and non-BAL RQQs for context. All 12 snapshot and 8/9 archival BAL RLQs are detected, with observed X-ray luminosities less than those of non-BAL RLQs having comparable optical/UV luminosities by typical factors of 4.1-8.5. (BAL RLQs are also X-ray weak by typical factors of 2.0-4.5 relative to non-BAL RLQs having both comparable optical/UV and radio luminosities.) However, BAL RLQs are not as X-ray weak relative to non-BAL RLQs as are BAL RQQs relative to non-BAL RQQs. While some BAL RLQs have harder X-ray spectra than typical non-BAL RLQs, some have hardness ratios consistent with those of non-BAL RLQs, and there does not appear to be a correlation between X-ray weakness and spectral hardness, in contrast to the situation for BAL RQQs. RLQs are expected to have X-ray continuum contributions from both disk-corona and small-scale jet emission. While the entire X-ray continuum in BAL RLQs cannot be obscured to the same degree as in BAL RQQs, we calculate that the jet is likely partially covered in many BAL RLQs. We comment briefly on implications for geometries and source ages in BAL RLQs.Comment: 48 pages, 5 tables, 14 figures, accepted by Ap