905 research outputs found
Punishment Correlations in a Multiple Schedule
Research indicates that punishment sometimes has discriminative as well as suppressive properties. The discriminative property of punishment usually has been exhibited by correlating punishment, with positive reinforcement, then testing for facilitative effects of punishment on responding in the absence of positive reinforcement. In the present study, punishment was correlated with one or the other of the two components of a multiple fixed-ratio schedule after the discrimination based on differential frequency of reinforcement had been formed. The correlation of punishment x^ith the components we.s reversed with the expectation that reversal of the correlations would reveal appropriate changes in responding in the newly punished component. Further tests were made of the presumed discriminative role of punishment by adding punishment to both schedule components during extinction. Punishment did suppress responding, although recovery of prepunishment response rate was observed in the high-frequency component of the multiple schedule as anticipated. However, evidence of a discriminative property of punishment was not obtained in any of the comparisons. Several explanations for the failure to find discriminative effects were considered. The most promising is an application of the Miller-Egger hypothesis to the effect that in a well-controlled multiple-schedule punishment is a redundant cue
The Influence of Russian Symbolists' Literature Studies on V. M. Zhirmunsky's Understanding of Poetics as an Academic Discipline
The article also deals with Zhirmunskiy's prologue to the book "Issues of the Theory of Literature" (1928), which helps shed new light on his evaluation of Russian symbolists in the final edition of the "Goals of Poetics". For example, in the late 1920s Zhirmunskiy views Bryusov's role in establishing poetics as an academic discipline in a slightly different way, compared to the initial text of the "Goals of Poetics". Thus, the purely theoretical aspect of comprehending the symbolists' heritage intertwines with the literary-aesthetic fight of those years. The understanding of poetics as an academic discipline by Zhirmunskiy, the formalists and in the literature studies of the 1910s-1920s in general goes back to the theoretical heritage of Russian symbolism.В статье рассматривается работа В. М. Жирмунского "Задачи поэтики", в которой отразилась динамика отношения ученого к литературоведческому наследию русского символизма
Improved computations for relationship inference using low-coverage sequencing data
Pedigree inference, for example determining whether two persons are second cousins or unrelated, can be done by comparing their genotypes at a selection of genetic markers. When the data for one or more of the persons is from low-coverage next generation sequencing (lcNGS), currently available computational methods either ignore genetic linkage or do not take advantage of the probabilistic nature of lcNGS data, relying instead on first estimating the genotype. We provide a method and software (see familias.name/lcNGS) bridging the above gap. Simulations indicate how our results are considerably more accurate compared to some previously available alternatives. Our method, utilizing a version of the Lander-Green algorithm, uses a group of symmetries to speed up calculations. This group may be of further interest in other calculations involving linked loci
Attosecond control of electron dynamics in carbon monoxide
Laser pulses with stable electric field waveforms establish the opportunity
to achieve coherent control on attosecond timescales. We present experimental
and theoretical results on the steering of electronic motion in a
multi-electron system. A very high degree of light-waveform control over the
directional emission of C+ and O+ fragments from the dissociative ionization of
CO was observed. Ab initio based model calculations reveal contributions to the
control related to the ionization and laser-induced population transfer between
excited electronic states of CO+ during dissociation
Image distortion in non perturbative gravitational lensing
We introduce the idea of {\it shape parameters} to describe the shape of the
pencil of rays connecting an observer with a source lying on his past
lightcone. On the basis of these shape parameters, we discuss a setting of
image distortion in a generic (exact) spacetime, in the form of three {\it
distortion parameters}. The fundamental tool in our discussion is the use of
geodesic deviation fields along a null geodesic to study how source shapes are
propagated and distorted on the path to an observer. We illustrate this
non-perturbative treatment of image distortion in the case of lensing by a
Schwarzschild black hole. We conclude by showing that there is a
non-perturbative generalization of the use of Fermat's principle in lensing in
the thin-lens approximation.Comment: 22 pages, 6 figures, to appear in Phys. Rev. D (January 2001
Physical pathways of nutrient supply in a small, ultraoligotrophic arctic lake during summer stratification
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110013/1/lno20065121107.pd
M. M. Bakhtin and the Russian Symbolists
В статье рассматривается влияние русских символистов, в том числе Андрея Белого, на М. М. Бахтина.This article deals with the influence that the Russian symbolists, including Andrey Bely, had on M. M. Bakhtin
Size-Resolved Characterization of Particles and Fibers Released during Abrasion of Fiber-Reinforced Composite in a Workplace Influenced by Ambient Background Sources
Active Layer Groundwater Flow: The Interrelated Effects of Stratigraphy, Thaw, and Topography
The external drivers and internal controls of groundwater flow in the thawed “active layer” above permafrost are poorly constrained because they are dynamic and spatially variable. Understanding these controls is critical because groundwater can supply solutes such as dissolved organic matter to surface water bodies. We calculated steady‐state three‐dimensional suprapermafrost groundwater flow through the active layer using measurements of aquifer geometry, saturated thickness, and hydraulic properties collected from two major landscape types over time within a first‐order Arctic watershed. The depth position and thickness of the saturated zone is the dominant control of groundwater flow variability between sites and during different times of year. The effect of water table depth on groundwater flow dwarfs the effect of thaw depth. In landscapes with low land‐surface slopes (2–4%), a combination of higher water tables and thicker, permeable peat deposits cause relatively constant groundwater flows between the early and late thawed seasons. Landscapes with larger land‐surface slopes (4–10%) have both deeper water tables and thinner peat deposits; here the commonly observed permeability decrease with depth is more pronounced than in flatter areas, and groundwater flows decrease significantly between early and late summer as the water table drops. Groundwater flows are also affected by microtopographic features that retain groundwater that could otherwise be released as the active layer deepens. The dominant sources of groundwater, and thus dissolved organic matter, are likely wet, flatter regions with thick organic layers. This finding informs fluid flow and solute transport dynamics for the present and future Arctic
Page charge of D-branes and its behavior in topologically nontrivial B-fields
The RR Page charges for the D(2p+1)-branes with B-field in type IIB
supergravity are constructed consistently from brane source currents. The
resulting Page charges are B-independent in the nontrivial and intricate way.
It is found that in topologically trivial B-field the Page charge is conserved,
but in the topologically nontrivial B-field it is no longer to be conserved,
instead there is a jump between two Page charges defined in each patch, and we
interpret this jump as Hanany-Witten effect.Comment: 25 pages, 4 figures, typos corrected and reference adde
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