41,998 research outputs found
Optimization of controlled environments for hydroponic production of leaf lettuce for human life support in CELSS
A research project in the food production group of the Closed Ecological Life Support System (CELSS) program sought to define optimum conditions for photosynthetic productivity of a higher plant food crop. The effects of radiation and various atmospheric compositions were studied
A survey of thermodynamic properties of the compounds of the elements CHNOPS Progress report, 1 Oct. - 31 Dec. 1966
Thermodynamic properties for compounds of the elements carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfu
A survey of thermodynamic properties of the compounds of the elements CHNOPS Eighth progress report, 1 Apr. - 30 Jun. 1966
Thermodynamic properties of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur compound
Midcourse maneuver operations program
Midcourse Maneuver Operations Program /MMOP/ computes the required velocity change to correct a spacecraft trajectory. The program establishes the existence of maneuvers which satisfy spacecraft constraints, explores alternate trajectories in the event that some out-of-tolerance condition forces a change in plans, and codes the maneuvers into commands
A study of possible sea state information in the sample and hold gate statistics for the GEOS-3 satellite altimeter
The statistical variations in the sample gate outputs of the GEOS-3 satellite altimeter were studied for possible sea state information. After examination of a large number of statistical characteristics of the altimeter waveforms, it was found that the best sea predictor for H-1/3 in the range of 0 to 3 meters was the 75th percentile of sample and hold gate number 11
Introduction - Exploring Foundations: Languages of Disability, Identity, and Culture
Produced by Hawai'i University Affiliated Program on Disabilities, University of Hawai'i at Manoa, Honolulu, Hawai'i, Frank Sawyer School of Management, Suffolk University, Boston, Massachusetts, and School of Social Sciences, The University of Texas at Dallas, Richardson, Texas for The Society for Disability Studies
Demonstration of wide band RF photonic transversal phase-shifter
A transversal phase-shifter using multiple MZMs is demonstrated. The device exhibits continuously variable phase-shift exceeding 360° at 2 GHz and amplitude uniformity within 3 dB over 0.2-2 GHz. The device stability and practicality are discussed
Orbital correlations in the pseudo-cubic \emph{O} and rhombohedral -phases of LaMnO
The local and intermediate structure of stoichiometric LaMnO has been
studied in the pseudocubic and rhombohedral phases at high temperatures (300 to
1150 K). Neutron powder diffraction data were collected and a combined Rietveld
and high real space resolution atomic pair distribution function analysis
carried out. The nature of the Jahn-Teller (JT) transition around 750 K is
confirmed to be orbital order to disorder. In the high temperature orthorhombic
() and rhombohedral () phases the MnO octahedra are still fully
distorted locally. The data suggest the presence of local orbitally ordered
clusters of diameter \AA (four MnO octahedra) implying
strong nearest neighbor JT anti-ferrodistortive coupling.Comment: 4 pages, 4 figures, submitted to Phys. Rev. Le
Drug cue reactivity involves hierarchical instrumental learning: evidence from a biconditional Pavlovian to instrumental transfer task
This is the final version of the article. Available from Springer Verlag via the DOI in this record.RATIONALE: Drug cue reactivity plays a crucial role in addiction, yet the underlying mechanisms are poorly understood. According to the binary associative account, drug stimuli retrieve an expectation of the drug outcome, which, in turn, elicits the associated drug-seeking response (S-O-R). By contrast, according to the hierarchical account, drug stimuli retrieve an expectation that the contingency between the drug-seeking response and the drug outcome is currently more effective, promoting performance of the drug-seeking response (S:R-O). METHODS: The current study discriminated between these two accounts using a biconditional Pavlovian-to-instrumental transfer (PIT) task with 128 alcohol drinkers. A biconditional discrimination was first trained in which two responses produced alcohol and food outcomes, respectively, and these response-outcome contingencies were reversed across two discriminative stimuli (SDs). In the PIT test, alcohol and food cues were compounded with the two SDs to examine their impact on percent alcohol choice in extinction. RESULTS: It was found that alcohol and food cues selectively primed choice of the response that earned that outcome in each SD (p < .001), and this effect was associated with participants' belief that cues signalled greater effectiveness of that response (p < .0001). CONCLUSIONS: The alcohol stimulus could not have selectively primed the alcohol-seeking response through binary S-O-R associations because the drug outcome was equally associated with both responses. Rather, the alcohol stimulus must have retrieved an expectation that the response-alcohol contingency available in the current context was more likely to be effective (S:R-O), which primed performance of the alcohol-seeking response.The work was supported by an ESRC PhD scholarship to Lorna Hardy
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